NSCI101

NSCI101 - General Chemistry Assignment 001 Elements are arranged in the periodic table in order of increasing atomic number. Select one: True False

Elements can be decomposed into smaller substances. Select one: True False

The number of electrons and protons are equal in number. Select one: True False

The -ium ending on the name of hydronium indicates that it is a cation from metal atoms. Select one: True False

How many significant figures are in 0.000187? Select one: a. 3

b. 5 c. 4 d. 6

Accuracy is a measure of how closely individual measurements are to the actual or true value, while precision refers as to how closely individual measurements are to one another. Select one: True False

What is the mass number of an atom that has 5 protons, 5 electrons and 6 neutrons? Select one: a. 11 b. 10 c. 16 d. None of the choices

Convert 35.6 degrees Celsius to Fahrenheit Select one: a. 96.1 degrees Fahrenheit b. 2 degrees Fahrenheit c. 308.75 degrees Fahrenheit d. 69.1 degrees Fahrenheit

Which of the following statement is correct?

Select one: a. Empirical formula shows the actual number of atoms in a molecule. b. Both of the given choices are correct c. No correct answer d. Molecular formula shows only the relative ratio of each of each atom in a molecule

Using the periodic table, which element is in Group 2A period 5? Select one: a. Ba b. N c. Ra d. Sr

Short Quiz 001 What is the name of the compound that has 2 nitrogen and 4 oxygen? Select one: a. dinitrogen tetroxide b. nitrogen (II) oxide c. nitrogen tetroxide d. binitrogen tetroxide

______________ are elements located in rows, while ________ are elements located in columns Select one: a. gases; period

b. period; group c. group; period d. no correct answer

Atomic number plus the number of neutrons is referred to as: Select one: a. Mass number b. Isotopes c. None of the choices d. Atomic number

Which ion is not correctly named? Select one: a. Ca2+, calcium (II) ion b. Fe3+, iron (III) ion c. Cr3+, chromium (III) ion d. O22-, peroxide ion

Which of the following statement is true regarding atoms? Select one: a. Every atom does not have net electrical charge, thus the number of electrons and protons are equal in number. b. Both protons and neutrons reside inside the atom's nucleus c. Nucleus contains majority of the mass of an atom d. None of the choices

e. All of the given choices are correct

Compute the area given the following measurements: 2.0546 cm and 4.3 cm. Express the answer in significant figures. Select one: a. 8.9 cm2 b. 8.8 cm2 c. 8.8348 cm2 d. 8.83 cm2

What is the mass number of an atom that has 2 protons, 2 electrons and 4 neutrons? Select one: a. 4 b. None of the choices c. 8 d. 6

Which of the following statement is not true according to Dalton's atomic theory ? Select one: a. None of the choices b. Atoms are can be created or destroyed in a chemical reaction. c. Compounds are made up of a combination of atoms of more than one element d. Elements are made up of extremely tiny particles called atoms. e. All atoms of a given element are the same, but atoms of one element are different from the atoms of all other elements.

Which of the following statement is true regarding matter? Select one: a. States of matter can be converted from one state to another by having changes in temperature b. Both of the given choices are correct c. No correct answer d. States of matter can be converted from one state to another by having changes in pressure

How many significant figures are in 5.070 x 103 g? Select one: a. 3 b. 2 c. 4 d. 5

Assignment 002 In a balanced chemical equation, the number of atoms of an element on the left side is always __________ the number of atoms on the right side. Select one: a. Equal to b. Less than c. Greater than d. Cannot be determined

The _______________________ states that mass in an isolated system is neither created nor destroyed by chemical reactions or physical transformations. Select one: a. Percent composition by mass b. Avogadro's number c. Law of conservation of mass d. Average atomic mass

The _______________________, is the percent by mass of each element in a compound. Select one: a. Mass percent b. None of the choices c. Percent composition by mass d. Both of these

Suppose synthesis of Al2O3 is done in the lab using 20.50 g of Al and excess of O2. Upon purification, 35.48 grams of Al2O3 is produced. What is the percent yield of Al2O3? Select one: a. 57.78% b. 22.90% c. 45.80% d. 91.58%

________ mass is used in case of ionic compounds that do not contain discrete molecular units. Select one: a. Average Atomic

b. Formula c. Molecular d. Atomic

The reactant that is used up first in a reaction is called the ____________ reagent. Select one: a. Excess b. Limiting c. Both of these

In a reaction, the amount of ____________ determines the amount of product. Select one: a. Both of these b. Limiting reagent c. Excess reagent

___________ is a process in which a substance or substances is transformed into one or more new substances Select one: a. Chemical reaction b. Percent composition by mass c. Percent yield d. Law of conservation of mass

Aluminum oxide, Al2O3, is synthesized by the reaction of aluminum, Al, and oxygen gas, O2. Which of the following equations correctly represent the reaction? Select one: a. 2Al + O3 → Al2O3 b. 2Al + 3O2 → 2Al2O3 c. Al + O2 → Al2O3 d. 4Al + 3O2 → 2Al2O3

________ is defined as the sum of the atomic masses in the molecule. Select one: a. Formula mass b. Average atomic mass c. Molecular mass/weight d. Atomic mass unit

Short Quiz 002 In a balanced chemical equation, the number of atoms of an element on the left side is always equal to the number of atoms on the right side. Select one: True False

The percent composition by mass of ferrous sulfide, FeS, is 50% Fe and 50% S. Select one: True

False

Given the percent composition by mass of all the elements in an unknown compound, we can always determine its molecular formula. Select one: True False

A percent yield of 100% is impossible to attain in the laboratory. Select one: True False

If 2 moles of AB4were made to react with 2 moles of C2, 1 moles of AC2 will be produced. Select one: True False

Iron, Fe, has an atomic mass of 55.85 amu therefore, the molar mass of Fe is 55.85 g/mol. Select one: True False

One mole of Phosphorus, with atomic mass of 30.97 amu, has greater number of atoms than one mole of Boron, with atomic mass of 10.81 amu. Select one:

True False

One mole of N2 contains 2*6.022 x 1023 molecules. Select one: True False

As long as we use stoichiometric amounts of reactants in a reaction carried out in the laboratory, we are guaranteed to get the theoretical yield of the reaction. Select one: True False

AB4+2C2->AC2+2B2C. If 100 grams of AB4 reacts with excess of C2, it will produce 100 grams of AC2. Select one: True False

Assignment 003 Which of the following statement is not true regarding kinetic molecular theory? Select one: a. Average kinetic energy of gas molecules is proportionate to absolute temperature. At any given temperature, gas molecules have exactly similar average kinetic energy. b. Energy can be transferred when molecules collide with one another. However, at constant temperature, the average kinetic energy remains unchanged.

c. Forces between gas molecules, whether attractive or repulsive, are negligible. d. Gases are composed of large numbers of molecules that are in constant, random motion. e. Total volume of all the gas molecules is negligible in relation to the total volume where the gas is contained. f. None of the choices Which of the following can increase the pressure of a gas? Select one: a. Lower velocity b. Bigger container c. Smaller container d. Smaller number of molecules Dalton's law of partial pressure states that constant temperature and volume, the total pressure of a gas is ____________ proportional to the number of moles of gas present. Select one: a. inversely b. sometimes inversely, sometimes directly c. directly

Which of the following increases as work increases? Select one: a. No correct answer b. Distance c. Both force and distance d. Force

What is an example of endothermic process? Select one: a. Combustion of gasoline b. Burning sugar c. Ice melting d. Combustion of gasoline and burning sugar

e. Evaporating water f. Ice melting and evaporating water What is defined as the amount of heat needed to raise the temperature of 1gram of the substance by 1K or 1C? Select one: a. Enthalpy b. Heat capacity c. Kinetic energy d. Specific heat Which gas law states that at constant pressure, the volume of a fixed amount of gas is directly proportional to its absolute temperature? Select one: a. Avogadro's Law b. Boyle's Law c. Charle's Law

___________________ is a combination of Boyle's, Charle's and Avogadro's laws. Select one: a. Dalton's Law of Partial Pressures b. No correct answer c. Kinetic Molecular Theory of Gases d. Ideal Gas Law

According to the kinetic molecular theory, average kinetic energy of gas molecules is proportional to absolute temperature. At any given temperature, gas molecules have exactly similar average kinetic energy. Select one: True False

Which of the following statement is true regarding Gas Laws?

Select one: a. All of the choices b. Avogadro's law states that at constant pressure, the volume of a fixed amount of gas is directly proportional to its absolute temperature c. Boyle's Law states that at a constant temperature, the volume of a fixed amount of gas is inversely proportional to its pressure d. Charle's Law states that at constant temperature and pressure, volume of gas is directly proportional to the number of moles of gas present

Short Quiz 003 Gases take up volume and shape of its container, are considered the least compressible state of matter and have the lowest density compared to solids and liquids. Select one: True False Partial pressure is defined as the amount of pressure exerted by each component gas in a mixture, which is independent of the pressure exerted by the other gases. Select one: True False According to the kinetic molecular theory, average kinetic energy of gas molecules is proportional to absolute temperature. At any given temperature, gas molecules have exactly similar average kinetic energy. Select one: True False Pressure is defined as the effect of a force applied to a surface and can be measured by means of a barometer or manometer. Select one: True False

Molar heat capacity is the amount of heat needed to raise the temperature of 1 mole of a substance by 1K or one degree celsius. Select one: True False

Charle's Law states that at a constant pressure, the volume of a fixed amount of gas is inversely proportional to its absolute temperature. Select one: True False Ideal Gas Law is expressed as PV=nRT. Select one: True False As the mass or speed increases, kinetic energy decreases. Select one: True False The internal energy of a system increases when heat is applied of work is done into it. Select one: True False Positive ΔH means that heat is lost from the system into its surroundings, while negative enthalpy ΔH means that heat is absorbed by the system from its surroundings Select one: True False

Long Quiz 001 Higher temperature in gas means higher ____________. Select one: a. None of the choices b. kinetic energy c. velocity d. Velocity and Kinetic energy

Suppose 20.50 g of Al reacts with excess O2, how many grams of Al2O3 is produced? (Molar Mass of Al2O3 is 101.96 g/mol) Select one: a. 154.94 grams b. 10.85 grams c. 38.74 grams d. 77.47 grams What is the name of the compound that has 2 sulfur and 10 fluorine? Select one: a. disulfurdecafluoride b. sulfur (II) fluoride c. bisulfurdecafluoride d. sulfur decafluorine

Compute the area given the following measurements: 3.7552 cm and 1.7 cm. Express the answer in significant figures. Select one: a. 6 cm2 b. 6.42 cm2 c. 6.4178 cm2 d. 6.4 cm2

Which gas law states that at a constant temperature, the volume of a fixed amount of gas is inversely proportional to its pressure? Select one: a. Boyle's Law b. Charle's Law c. Avogadro's Law

Which of the following statement is true regarding Dalton's atomic theory? Select one: a. Compounds are made up of a combination of atoms of more than one element b. All of the choices c. Elements are made up of extremely tiny particles called atoms. d. All atoms of a given element are the same, but atoms of one element are different from the atoms of all other elements. e. Atoms are can neither be created nor destroyed in a chemical reaction.

How many significant figures are in 0.00002 Select one: a. 6 b. 3 c. 5 d. 1

Kinetic energy is expressed as; Select one:

How many significant figures are in 4.0300 x 103 g? Select one: a. 4 b. 2 c. 5 d. 3

How many grams of Carbon are in 600 grams of Resveratrol? (Note: Resveratrol, C14H12O3 is a compound usually found in grapes and some berries. The molar mass of this compound is 228.26 g/mol.) Select one: a. 36.8 grams b. 815.21 grams c. 63.96 grams d. 441.97 grams

Resveratrol, C14H12O3 is a compound usually found in grapes and some berries. The molar mass of this compound is 228.26 g/mol. How many moles of resveratrol are in 600 grams of sample? Select one: a. 5.26 moles b. 0.76 moles c. 0.38 moles d. 2.63 moles Using the periodic table, which element is in Group 4A period 6? Select one: a. Ti b. V c. Sn d. Pb

In reference to item 13, suppose synthesis of Al2O3 is done in the lab using 20.50 g of Al and excess of O2. Upon purification, 30.33 grams of Al2O3 is produced. What is the percent yield of Al2O3? Select one: a. 147.95% b. 67.58% c. 78.29% d. 39.15% What is defined as the described as the sum of the internal energy and product of pressure and volume in a system? Select one: a. Specific heat b. Kinetic energy c. Enthalpy d. Heat capacity

Which of the following is true regarding specific heat? Select one: a. Defined as the amount of heat needed to raise the temperature of 1 gram of the substance by 1K or 1°C b. No correct answer c. Defined as the amount of heat needed to raise the temperature of 1 mole of a substance by 1K or 1°C. d. Both of the given statements are true What is the mass percent of Hydrogen, H, in resveratrol? Select one: a. 18.83% b. 5.31% c. 5.26% d. 19.02%

Which of the following is the correct formula of sulfurous acid? Select one: a. H2SO3 b. H2S c. HSO3 d. HS

Which of the following statement is true regarding the periodic table? Select one: a. Both of the given statements are correct b. No correct answer c. Metalloids are elements that possess both metallic and non-metallic properties d. Non-metals can be found on the upper right side of the periodic table

How many moles of Al is needed to produce 4 moles of Al2O3 Select one: a. 8 moles b. 1 mole c. 2 moles d. 4 moles

How many atoms of oxygen are in 1 mole of Resveratrol? (Note: Resveratrol, C14H12O3 is a compound usually found in grapes and some berries. The molar mass of this compound is 228.26 g/mol.) Select one: a. 2.01 x 1023 b. 18.06 x 1023 c. 6.02 x 1023 d. 12.04 x 1023

The empirical formula of an unknown compound was determined to be CH2O. A separate analysis to determine the molar mass was done. Results show that the molar mass is 360.36 g/mol. What is the molecular formula of the unknown compound? Select one: a. C6H12O6 b. C12H24O12 c. Cannot be determined d. C3H6O3 The difference between the mass number and the atomic number equals the number of ________________ in an atom. Select one: a. Electrons b. Protons c. Neutrons How many significant figures are in 0.0054 Select one: a. 3 b. 5 c. 2 d. 4 Which gas law states that at at constant temperature and pressure, volume of gas is directly proportional to the number of moles of gas present. Select one: a. Ideal Gas Law b. Charle's Law c. Boyle's Law d. Avogadro's Law

Which of the following statement is not true regarding kinetic molecular theory? Select one:

a. Average kinetic energy of gas molecules is proportionate to absolute temperature. At any given temperature, gas molecules have exactly similar average kinetic energy. b. Energy can be transferred when molecules collide with one another. However, at constant temperature, the average kinetic energy remains unchanged. c. Forces between gas molecules, whether attractive or repulsive, are negligible. d. Total volume of all the gas molecules is negligible in relation to the total volume where the gas is contained. e. Gases are composed of large numbers of molecules that are in constant, random motion. f. None of the choices

Which of the following statement is true regarding balancing chemical equations? Select one: a. Both of the given statements are correct b. No correct answer c. Balance first those elements that appear in only one reactant and one product. Then, balance elements that appear in more than one reactant and product. d. The common convention for balanced equations is to use the smallest whole numbers

Dalton's law of partial pressure states that constant _____________ and volume, the total pressure of a gas is directly proportional to the number of moles of gas present. Select one: a. pressure b. distance c. any of the given choices is correct d. temperature Copper, Cu, has two stable isotopes, 63Cu with atomic mass of 62.9 amu and 65Cu with atomic mass of 64.93 amu. The average atomic mass of Cu is 63.54. What are the percent abundances of the two isotopes? Select one: a. 1% 63Cu and 99% 65Cu b.

99% 63Cu and 1% 65Cu c. 30.5% 63Cu and 69.5 65Cu d. 69.5% 63Cu and 30.5 65Cu

Which of the following statement is true regarding Ideal Gas Law? Select one: a. b. All of the choices c. is a combination of Boyle’s, Charle’s and Avogadro’s laws d. Expressed as PV=nRT

Which of the following statement is not correct? Select one: a. Empirical formula shows the actual number of atoms in a molecule. b. None of the choices c. Both of the given choices are correct d. Molecular formula shows only the relative ratio of each of each atom in a molecule

Assignment 004 The f-subshells of transition metals are incompletely filled. Select one: True False The electron configuration influences the properties of the elements. Select one: True

False Energy levels of orbitals determine the actual arrangement of electrons in atoms. Electrons will fill first the most stable orbitals. Select one: True False Henry Moseley proposed the law of octaves in which he explains that the atomic masses of the elements when arranged in ascending order, elements falling in every eight position were deemed to have the same properties. Select one: True False

The magnetic quantum number describes the size of the orbital. It also indirectly describes the energy of an orbital. Select one: True False Effective nuclear charge is the nuclear charge felt by an electron when both the actual nuclear charge and the repulsive effects of the other electrons are taken into account. Select one: True False Group IA elements have the lowest ionization energies. Select one: True False According to the quantum theory, energy is always expressed in integral multiples. Select one: True False

The energy of a single photon is described as E = hv Select one: True False

Valence electrons are also known as the innermost electrons. Select one: True False

Short Quiz 004 What theory explains that when certain metals are exposed to light of at least a certain minimum frequency, electrons are ejected from its surface. Select one: a. Heisenberg Uncertainty Principle b. Aufbau Principle c. Photoelectric Effect d. Bohr's theory of the hydrogen atom

Direction : Identify if the following elements are metal, non-metal or metalloids: Bismuth Select one: a. Metal b. Non-metal c. Metalloids

Which of the following is true about d orbitals? Select one: a. Both of the given statements are correct

b. All d orbitals are spherical in shape. c. All d orbitals have 2 different shapes. d. No correct answer

Direction : Identify if the following elements are metal, non-metal or metalloids: Germanium Select one: a. Non-metal b. Metalloids c. Metal

Direction : Identify if the following elements are metal, non-metal or metalloids: Tellurium Select one: a. Metalloids b. Non-metal c. Metal

Direction : Identify if the following elements are metal, non-metal or metalloids: Oxygen Select one: a. Non-metal b. Metal c. Metalloids

Which of the following quantum numbers describes the orientation of the orbitals? Select one: a. Magnetic quantum number b. Principal quantum number

c. Angular momentum quantum number

Which theory states that the farther away the electron is from the nucleus, the higher the excited state is? Select one: a. Heisenberg Uncertainty Principle b. Aufbau Principle c. Bohr's theory of the hydrogen atom d. Photoelectric Effect

Which of the following rules is not true with regards to assigning maximum number of electrons to orbitals (given n)? Select one: a. Both of the statements are correct b. The principal quantum number (n) also dictates the number of subshells (two values of l) c. No correct answer d. The number of orbitals is determined by the angular quantum number (l), computed as 2l + 1.

Valence electrons are also known as the innermost electrons. Select one: True False

Assignment 005 In Lewis dots symbols, the number of valence electrons indicated in each element is the same as with their group number, except: Select one: a. Hydrogen b. Helium

c. Potassium d. Carbon This is a type of bond observed with two atoms sharing a pair of electrons. Select one: a. Triple bond b. Ionic bond c. Covalent bond d. Double bond

What elements tend to form anions in an ionic bond? Select one: a. None of these b. Alkali metals c. Both of these d. Halogens In the octet rule, how many electrons are expected in the valence shell? Select one: a. Five b. Eight c. Six d. Seven What is the energy required to completely break a mole of solid ionic compound into its individual gaseous ions? Select one: a. Lattice energy b. Potential energy c. Formal charge d. Ionization energy This refers to the capacity of an atom to attract electrons to itself. Select one:

a. Electronegativity b. Ionization energy c. Bond enthalpy d. Lattice energy Resonance structure are defined as two or more Lewis structures representing a particular molecule. Select one: a. True b. False Lewis dot symbols is the system used for writing chemicals, with dots written around chemical symbols to represent valence electrons? Select one: a. True b. False This describes the distance of nuclei of two covalently bonded atoms. Select one: a. Bond order b. Bond polarity c. Bond length d. Electronegativity In Lewis symbols, what are written around chemical symbols to represent valence electrons? Select one: a. Hyphen b. Colon c. Dots d. Comma

Short Quiz 005 What factor affect electronegativity?

Select one: a. Distance between nuclei b. Ionization energy c. Electron affinity and Ionization energy d. Electron affinity

Which of the following affects the amount of lattice energy needed in breaking an anion bond? Select one: a. Number of protons b. Distance between two atoms c. Product of charges of the two ions d. Product of charges of the two ions and Distance between two atoms

What factor affect electronegativity? Select one: a. Electron affinity b. Distance between nuclei c. Ionization energy d. Electron affinity and Ionization energy

Why can't we write Lewis structures for lanthanides, actinides, and transition metals? Select one: a. All of the choices b. Because of the number of electrons not equal to eight c. None of the choices d. Because of their incompletely filled inner shells

What is the energy required to completely break a mole of solid ionic compound into its individual gaseous ions? Select one: a. Bond enthalpy

b. Bond dissociation energy c. None of the choices d. Lattice energy

This refers to the capacity of an atom to attract electrons to itself. Select one: a. Electronegativity b. Bond length c. Bond polarity d. None of the choices

This is a type of bond observed with two atoms sharing a pair of electrons. Select one: a. Ionic bond b. None of the choices c. All of the choices d. Covalent bond

This type of bond happens when an electron from an atom transfers to another atom, forming ions and creating electrostatic attraction: Select one: a. None of the choices b. All of the choices are correct c. Ionic bond d. Covalent bond

Which of the following is not an exception to the octet rule? Select one: a. Molecules with odd number of electrons b. Molecules with eight electrons in its valence shell

c. Molecules with less than an octet number of electrons d. Molecules with more than an octet number of electrons

We cannot write Lewis symbols for what group of elements? Select one: a. Transition metals b. Lanthanides c. All of the choices d. Actinides

Assignment 006 Supersaturated solutions contain more than the maximum amount of solvent in a solution. Select one: True False The freezing-point temperature of a solution is lower as compared to its pure solvent. Select one: True False Solubilities of solids and gases affect differently with temperature. Select one: True False The main difference between the condensed states and the gaseous state of matter is the distance between molecules. Select one: True False

Due to little space in between molecules, solids and liquids lack shapes and volume. Select one: True False Colligative properties depend on the nature of the substances in a solution. Select one: True False The stronger the intermolecular forces, the higher the surface tension. Select one: True False The lack of molecules above the surface of liquids causes them to tighten and form an elasticlike film. Select one: True False The boiling-point temperature of a solution is higher than its pure solvent. Select one: True False Water flow easier than honey because of its higher viscosity. Select one: True False

Short Quiz 006 Which of the following intermolecular forces are observed in polar molecules?

Select one: a. Dispersion forces b. Dipole-dipole forces c. Ion-dipole forces d. Dipole-dipole forces and Ion-dipole forces

Which of the following is not a type of solution? Select one: a. Saturated solution b. Unsaturated solution c. Hypersaturated solution d. Supersaturated solution

What factor affects the polarizability of a certain nonpolar molecule? Select one: a. The number of electrons in the cloud b. All of the choices c. How dispersed are the electrons surrounding the molecule d. The molar mass of the molecule

Molecules in gases, under normal conditions, is observed to: Select one: a. All of the choices b. Repel each other c. Exert great attractive forces together d. Have no great interaction between them This is a method used to distinguish a solution from a colloid, where light is beamed in a substance and observed if it would scatter due to dispersed particles observable in a colloid: Select one: a. Crystallization b. Van der Waals effect

c. Effervescence d. Tyndall effect

What is the collective term for forces that attracts molecules together? Select one: a. Dispersion forces b. Intramolecular forces c. Intermolecular forces d. Dipole interaction

Which of the following is NOT a type of concentration unit? Select one: a. Boiling Point Elevation b. Mole Fraction c. Molality d. Percent by Mass

This refers to a process where molecules of a solvent pass through a semipermeable membrane; Select one: a. Osmotic pressure b. Osmosis c. Effervescence d. None of the above

What traits can be observed with gases, due to the large amount of space in between molecules and the lack of interaction between them? Select one: a. Gases are incompressible b. None of the choices c. Gases are easily compressible

d. Gases have high density

What can affect the viscosity of a certain liquid? Select one: a. Distance between molecules b. Temperature c. None of the choices d. Number of electrons

Assignment 007 In the following chemical reaction, what can be done to maintain the forward reaction?

Select one: a. Increase concentration of PCl3 b. Decrease concentration of PCl3 c. Increase concentration of PCl5 d. Decrease concentration of Cl2

Differential Rate Law expresses how the reaction rate depends on the concentration while the Integrated Rate Law expresses how the concentrations depend on time. Select one: True False

Which of the following does not affect chemical equilibrium? Select one: a. Pressure b. Time

c. Temperature d. Concentration The direction of the reaction favored when stress is applied is towards the direction where the stress is lessened. Select one: True False How does temperature affect rate constants? Select one: a. Increasing the temperature also speeds up the reaction, hence, increasing the rate constants. b. Increasing the temperature also slows up the reaction, hence, decreasing the rate constants. c. Increasing the temperature also speeds up the reaction, hence, decreasing the rate constants. d. Increasing the temperature also slows up the reaction, hence, increasing the rate constants. Increasing the temperature also speeds up the reaction, hence, increasing the rate constants Select one: True False

Chemical equilibrium is the state in which there is no apparent change in the products and reactants over time, and the free energy of the reaction is at its lowest. Select one: True False

Which of the following describes the relation between reactant concentration and time in the following equation?

Select one:

a. PCl3 and Cl2 decrease over time. b. PCl5 decrease over time. c. PCl5 increase over time. d. PCl3 and Cl2 increase over time.

A homogeneous catalysis occurs using a catalyst that has a different phase as the reacting molecules while a heterogeneous catalysis occurs when a catalyst has the same phase as the reactants. Select one: True False

Concentration of reactants is reduced over the course of reaction. Select one: True False

Short Quiz 007 The differential rate law expresses how the reaction depends on concentration while integrated rate law expresses how concentration depends on temperature. Select one: True False

Hydrogenation of ethylene to ethane using Palladium as a catalyst is considered a heterogeneous catalysis. Pd

C2H2 (g) Select one:

+

H2(g) -> C2H4 (g)

True False

For the given reaction mechanism, NO3 is one of the final products. k1

NO2(g)

+

NO2(g) -> NO3(g)

+

NO(g)

k2

NO3(g)

+

CO (g) -> NO2(g)

+

CO2(g)

Select one: True False In order for a given exothermic chemical reaction to proceed, heat must be supplied for the molecules to collide. Select one: True False During a chemical reaction, the concentration of the reacting species increase over time while it is being consumed. Select one: True False Chemical equilibrium is the state at which the free energy of the reaction is at its highest possible value. Select one: True False Changes in concentration, temperature, pressure, and time are important factors to consider in chemical equilibrium. Select one:

True False Le Chatelier's principle states that if stress (or a change in condition) is imposed on a system at equilibrium, the equilibrium position shifts to a direction that tends to lessen the stress. Select one: True False During a chemical equilibrium, concentrations of products and reactants no longer have apparent change. Select one: True False The Brownian Model explains how the temperature affects the rate constants of a chemical reaction: Select one: True False

Long Quiz 002 Why can glass be filled slightly above the rim with water without overflowing? Select one: a. Because of the water's temperature b. Because of surface tension c. Because of atmospheric pressure d. Because of nonpolar molecules Explain the relationship between the number of bonds and the distance between bonded molecules. Select one: a. The number of bonds in a molecule has no impact on the distance of molecules. b. The higher the number of bonds in a molecule, the farther the distance of molecules.

c. The higher the number of bonds in a molecule, the shorter the distance of molecules. d. All of the above

Which of the following statement is true regarding Boh's Theory of the Hydrogen Atom? Select one: a. The electron is only allowed to occupy orbits of specific energies. b. All of the above c. The farther away the electron is from the nucleus, the higher the excited state is. d. Principal quantum number is expressed in integers

Which of the following statement is true regarding Tyndall effect? Select one: a. It is possible to observe this with solutions b. All of the above c. It is a method used to distinguish a solution from a colloid, where light is beamed in a substance and observed if it would scatter due to dispersed particles observable in a colloid. d. None of the above Which of the following is TRUE? Select one: a. Solutions already have more disordered molecules as compared to its pure solvent counterparts. b. Having higher solute concentrations causes lower vapor pressures. c. All of the above d. Solutions need a higher boiling point to evaporate as compared to their pure solvent counterparts

Given the following concentrations for the decomposition of NO2 compute for the rate of the reaction in terms of the reactant, NO2. Time(±1s) 200 250 Select one:

NO2 0.0048 0.0043

NO2 0.0052 0.0057

O2 0.0026 0.0029

a. – 1.0 x 105mol L-1 s-1 b. – 1.0 x 10-5mol L-1 s-1 c. + 1.0 x 10-5mol L-1 s-1 d. – 1.0 x 10-5mol Ls What is an induced dipole moment? Select one: a. An induced dipole is caused when a nonpolar molecule creates a temporary dipole moment, due to a disturbance in the distribution of electrons. b. None of the above c. An induced dipole is a previous dipole molecule turned into a nonpolar one d. An induced dipole molecule has a permanent positive and negative charge. What is a supersaturated solution? Select one: a. A solution containing solute lower than the maximum capacity a solvent can dissolve b. None of the above c. A solution containing solute more than the maximum capacity a solvent can dissolve d. A solution having the maximum amount of solute a solvent can dissolve During a chemical reaction, what happens to the concentration of the reactants? Select one: a. decreases b. nothing happens c. exponentially increases d. linearly increases The difference between the colligative properties of electrolyte and nonelectrolyte solutions is the breaking up of solute particles in a solution. This is quantified and added to computation of concentration units using the: Select one: a. None of the above b. van't Hoff factor c. London factor d. van der Waals factor

Which of the following statement is true? Select one: a. The trend of effective nuclear charge is increasing as one goes from top to bottom of a particular group of element in a periodic table. b. The size of an ionic compound is influenced by the sizes of its cation or anion c. All of the choices d. None of the choices

Which of the following is an exception to the octet rule? Select one: a. Molecules with less than an octet number of electrons b. Molecules with more than an octet number of electrons c. Molecules with odd number of electrons d. All of the above What is the relationship between intermolecular forces and surface tension? Select one: a. Intermolecular forces have no impact on surface tension b. Stronger intermolecular forces result in higher surface tension c. Weaker intermolecular forces result in higher surface tension d. Stronger intermolecular forces result in lower surface tension

What is the relationship between solubility of solids and temperature? Select one: a. Solubility of solids is not affected by temperature b. None of the choices c. Solubility of solids decrease with temperature d. Solubility of solids increase with temperature. What is the difference between homogeneous and heterogeneous catalysis? Select one: a. None of the above

b. A heterogeneous catalysis occurs when gaseous reactants are adsorbed on the surface of a solid catalyst while a homogeneous catalysis occurs when reactants and catalyst have the same phase. c. A heterogeneous catalysis occurs when reactants and catalyst have the same phases while a homogeneous catalysis occurs when reactants and catalyst have the different phase. Which of the following affects chemical equilibrium? Select one: a. All of the above b. Concentration c. Pressure d. Temperature

Which of the following concentration units is NOT independent of temperature? Select one: a. Percent by mass b. All of the above c. Molarity d. Molality Why do some covalently bonded molecules turn out to be bipolar? Select one: a. Electrons tend to form bonds and stick together in one place b. Electrons would spend more time in one atom than the other. This creates the polarity. c. Electrons cause attraction with protons, causing them to have increased influence in the molecule d. None of the above Which of the following best describes the Le Chatelier's Principle? Select one: a. Chemical reactions occur when molecules collide with sufficient kinetic energy. b. A body in motion will remain in motion unless an outside force acts on it. c. If stress is imposed on a system at equilibrium, the equilibrium position of the reaction shifts to a direction that tends to lessen the stress. d. A body at rest will remain at rest unless an outside force acts on it.

When does a chemical equilibrium occur? Select one: a. When products are no longer produced. b. When free energy of the reaction is at its highest possible value. c. When reactants are no longer consumed. d. When free energy of the reaction is at its lowest possible value.

In the following reaction, which happens first? NO2(g)

+

CO (g)

NO(g)

+

CO2(g)

Select one: a. NO2(g)

+

CO2 (g)

b. NO2(g)

+

NO2(g)

c. NO(g) d. NO3(g)

+ +

NO2(g)

-> ->

->

NO3g)

+

CO (g)

NO3(g)

+

NO(g)

NO2(g)

+

CO (g) -> NO2g)

+

NO(g) CO2(g)

Which of the following statement is true? Select one: a. All elements in Group 3A are metals. b. None of the above c. Group 4A elements have an electronic configuration of ns1 ,n≥2. d. Group 2A elements have the highest first ionization energy. Which of the following group of elements are Lewis structures not applicable? Select one: a. Lanthanides b. All of the above c. Transition metals d. Actinides

Which of the following rules is true with regards to assigning maximum number of electrons to orbitals (given n)?

Select one: a. The number of orbitals is determined by the angular quantum number (l), computed as 2l + 1. b. All of the above c. None of the above d. The principal quantum number (n) also dictates the number of subshells (two values of l)

Which of the following statements is true with regard to the relationship of lattice energy with the atoms' charges and the distance between them? Select one: a. Lattice energy is inversely proportional to the product of their charges b. All of the above c. Lattice energy is inversely proportional to the distance of separation between them. d. None of the above

Which of the following statement is true? Select one: a. All d orbitals, compared to s and p orbitals have 2 different shapes b. None of the above c. All of the above d. All p orbitals has 2 lobes on opposite sides of the nucleus What is the relationship between polarizability and intermolecular forces? Select one: a. The higher the polarizability of a certain molecule, the stronger the intermolecular force it creates. b. The higher the polarizability of a certain molecule, the weaker the intermolecular force it creates. c. The lower the polarizability of a certain molecule, the stronger the intermolecular force it creates. d. None of the above Explain the relationship with bond enthalpy and the number of bonds. Select one:

a. The higher the number of bonds in a molecule, the higher the needed bond dissociation energy to break them. b. The number of bonds in a molecule has no effect on bond dissociation energy c. None of the above d. The higher the number of bonds in a molecule, the lower the needed bond dissociation energy to break them. We can write Lewis symbols for what group of elements? Select one: a. Lanthanides b. None of the above c. Transition metals d. Actinides The following model explains how the temperature affects the rate constants of a chemical reaction: Select one: a. Collision Model b. Rutherford's Atomic Model c. Crystalline Model d. Brownian Model

Assignment 008 A 0.10 M Benzoic acid is prepared in water at 25°C. Calculate the concentration of the acid and conjugate base, benzoate, in the solution at equilibrium. (Ka = 6.3×10-5) Select one: a. benzoic acid = 0.098 M; benzoate = 0.002 M b. benzoic acid = 0.008M; benzoate = 0.001M c. benzoic acid = 0.089; benzoate = 0.02M d. benzoic acid = 0.010M; benzoate = 0.003M

Classify whether the following is Brønsted acid or base:

H2SO4 Select one: a. Acid b. Base Calculate the pH and pOH of a solution containing 3.4×10-5M H+. Select one: a. pH = 19.36; pOH = 10.09 b. pH = 4.47; pOH = 9.53 c. pH = 10.09; pOH = 19.36 d. pH = 9. 53; pOH = 4.47

Arrange the following acids from strongest to weakest using the given ionization constants

Select one: a. H2CO3>H3PO3> HNO2> NH4+> HC6H6O6b. HNO2> H2CO3>H3PO3> NH4+> HC6H6O6 c. H3PO3> HNO2> H2CO3> NH4+> HC6H6O6d. H3PO3> HNO2> H2CO3> HC6H6O6->NH4+

Consider the reaction below (NH4)2SO4(s)

2NH4+(aq) + SO42-(aq)

Write the formula for Ksp Select one:

a. Ksp = [NH4+(aq)][SO42-(aq)]2 b. Ksp = [NH4+(aq)]2[SO42-(aq)]2 c. Ksp = [NH4+(aq)]2[SO42-(aq)] d. Ksp = [NH4+(aq)][SO42-(aq)]

Classify whether the following is Brønsted acid or base: HCN Select one: a. Acid b. Base

The solubility of a sodium chloride in water at 25 degrees Celsius is 357g/L. What is the molar solubility of NaCl? Select one: a. 6.20M b. 4.67M c. 5.3 M d. 6.11M

Classify whether the following is Brønsted acid or base: H2CO3 Select one: a. Acid b. Base

Classify whether the following is Brønsted acid or base: NaNH2 Select one: a. Base

b. Acid

Classify whether the following is Brønsted acid or base: KOH Select one: a. Acid b. Base

Short Quiz 008 It is assumed that strong acids and bases completely ionize, meaning, all reactants are converted into products and there is no reactant left. That is why they have no ionization constants. Select one: True False Bond strength is the only factor affecting the strength of acids. Select one: True False A strong acid or base will also have a strong conjugate. Select one: True False At 25°C, in an acidic condition, Kw will always be less than 1.0×10-14. Select one: True False

Arrhenius base is a proton acceptor. Select one: True False

Henderson-Hasselbalch equation is the equation relating between pH and pKa. Select one: True False Equivalence point is the point in acid-base titration where the concentration of the acid is equal to the concentration of the base. Select one: True False

The concentration of AgNO3(s) should be included in the expression of Ksp for its solubility calculation because the molar concentration of the solid changes based on its amount. Select one: True False Amphoteric property is defined as the ability of a compound to function as a base or as an acid, depending on the solution. Select one: True False Le Chatelier's Principle governs the pH and common ion effect in solubility. Select one: True False

Assignment 009

Other name for the first law of thermodynamics. Select one: a. Law of Conservation of Energy b. Enthalpy c. Conversion of Energy d. Spontaneous Process

Compute the change of internal energy of a certain process in which 3000 J of heat is added to a system while the system does work equivalent to 6000 J by expanding against the surrounding atmosphere. Select one: a. -9000J b. -3000J c. 9000J d. 3000J

Which of the following statement is true? Select one: a. The Law of Conservation of Energy, states that energy cannot be created nor destroyed. b. All of the above c. The Second Laws states that the entropy of the entire universe in an isolated system will never decrease d. The Third Law-Nernst's theorem states that the entropy of a system approaches a constant value as the temperature approaches zero _____________ measures the randomness within a system. Select one: a. Heat b. Enthalpy c. Gibbs Free Energy d. Entropy

____________ is the ability to do work Select one: a. Heat b. Enthalpy c. Energy d. Entropy

Compute the change in internal energy of a certain process which gives off 300J of heat with 600J of work done on the system. Select one: a. 300J b. 200J c. 500J d. 400J A melting ice is an example of the first law of thermodynamics. Select one: True False _______________can be used to calculate the maximum reversible work at a constant temperature and pressure. Select one: a. Gibbs Free Energy b. Free Energy Change c. Kelvin d. Enthalpy

Compute for the work done if the change in internal energy is equals to 500J while giving off 350J of heat. Select one: a. -850J b. -150J c. 150J

d. 850J What are the types of systems Select one: a. Open System b. Isolated System c. Closed System d. All of the above

Short Quiz 009 When ΔS > 0 and ΔH > 0, the process will be ___________________ at high temperatures. Select one: a. Spontaneous b. Hard to tell c. None of the above d. Non-spontaneous Thermodynamics historically was developed out of the desire to increase the efficiency of the earlier steam engines. Select one: True False This law simply means that even if a system may gain or losses energy from its surroundings its total energy will still remain constant. Select one: a. The Second Law of Thermodynamics b. The Law on Conservation of Energy c. The Third Law of Thermodynamics d. The Law on Spontaneous Processes He was referred to be the Father of Thermodynamics. Select one:

a. Rudolf Julius Emmanuel Clausius b. Nicolas Leonard SadiCarno c. Julius Robert von Mayer d. Lord Kelvin

He was the first to formulate a concise definition of thermodynamics in 1854 which stated, "Thermo-dynamics is the subject of the relation of heat to forces acting between contiguous parts of bodies, and the relation of heat to electrical agency. Select one: a. Julius Robert von Mayer b. Lord Kelvin (William Thomson) c. Rudolf Julius Emmanuel Clausius d. Nicolas Leonard SadiCarno

He was a German physicist and a mathematician and one of the crucial founder of thermodynamics stated that heat by itself cannot pass from a colder to a hotter body Select one: a. Lord Kelvin b. Julius Robert von Mayer c. Nicolas Leonard SadiCarno d. Rudolf Julius Emmanuel Clausius When ΔS > 0 and ΔH < 0, the process is _________________________. Select one: a. Hard to tell b. None of the above c. Non-spontaneous d. Spontaneous It states that the entropy of a system approaches a constant value as the temperature approaches zero. Select one:

a. Spontaneous Processes b. The Law on Conservation of Energy c. The Second Law of Thermodynamics d. Nernst's Theorem It is also called as the Nernst's Theorem. Select one: a. Enthalpy b. Spontaneous Processes c. The Second Law of Thermodynamics d. The Third Law of Thermodynamics It would be impossible to perform work that results in an energy output greater than the energy input. Select one: True False

Assignment 010 From the given pairs, determine which pair is the anode. Select one: a. Co/CoCl3 b. Fe/FeCl3

From the given pairs, determine which pair is the anode. Select one: a. Fe/FeSO4 b. Ni/NiSO4

From the given pairs, determine which pair is the anode.

Select one: a. Zn/ZnSO4 b. Cu/CuSO4

Determine each nuclear transmutation Sr → 86Kr

90

Select one: a. Positron Emission b. Beta emission c. K-Capture d. Alpha emission

From the given pairs, determine which pair is the anode. Select one: a. Pb/PbSO4 b. Hg/HgSO4

Determine each nuclear transmutation : 55

Fe → 55Mn

Select one: a. Beta emission b. Alpha emission c. Positron Emission d. K-Capture

From the given pairs, determine which pair is the anode. Select one: a. Cu/CuSO4 b. Pb/PbSO4

Determine each nuclear transmutation 106

Ru → 106Rh

Select one: a. K-Capture b. Positron Emission c. Beta emission d. Alpha emission

Determine each nuclear transmutation : 235

U → 231Th

Select one: a. Beta emission b. Positron Emission c. K-Capture d. Alpha emission

Determine each nuclear transmutation : 137

Cs → 137Xe

Select one: a. Alpha emission b. K-Capture c. Beta emission d. Positron Emission

Short Quiz 010 True or False: Uranium-235 and Plutonium-235 are isotopes Select one: True

False

Determine the oxidation state of the mentioned element in the given compound : Chromium in H2CrO4 Select one: a. +6 b. +2 c. -5 True or False: Alpha emissions result in the release of gamma rays. Select one: True False

Determine the oxidation state of the mentioned element in the given compound : Manganese in KMnO4 Select one: a. -2 b. +4 c. +7 True or False: The number of neutrons determines the identity of the element. Select one: True False

Determine the oxidation state of the mentioned element in the given compound : Arsenic in H2AsO4 Select one: a. +7

b. -1 c. +6 True or False: Electron capture decay results in the decrease in the atomic number. Select one: True False True or False: Beta emission results in the formation of an element with 1 additional neutron Select one: True False

Determine the oxidation state of the mentioned element in the given compound : Nickel in NiCl2 Select one: a. +6 b. +1 c. +2

Determine the oxidation state of the mentioned element in the given compound : Zinc in ZnF2 Select one: a. -1 b. -2 c. +2

Long Quiz 003 Please mark the correct answer

Which of the following solutions can act as a buffer? Select one: a. Na2SO4/NaHSO4 b. Na2HPO4/NaH2PO4 c. All of the above d. KCN/HCN Please mark the correct answer When a strong acid and a strong base reacts, the equivalence point is at neutral range. If the reaction is between a strong base and a weak acid, the equivalence point is Select one: a. acidic b. basic c. neutral d. Cannot be determined Choose the correct answer for each question below

Please mark the correct answer Calculate the pH and pOH of a solution containing 5.7×10-6M H+. Select one: a. All of the above b. None of the above

c. pH = 5.24 d. pOH = 8.76 Please mark the correct answer Multiple choice: Which of the following will produce neutral solutions in water? Explain. Select one: a. ammonium chloride b. potassium nitrate c. sodium acetate

Determine if the transformation is an Oxidation, Reduction or Neither : Chromium, Cr2O72-→ CrO42Select one: a. Reduction b. Neither c. Oxidation

Determine if the transformation is an Oxidation, Reduction or Neither : Manganese, MnO2 → MnO4Select one: a. Neither b. Oxidation c. Reduction

Please mark the correct answer Aside from water, aluminum oxide is amphoteric. Which equation is correct? XYZ. Al2O3(s) + 6HCl(aq) ---------> 2AlCl3(aq) + 3H2O(l) YZX. Al2O3(s)

--------->

2Al + 3O

ZXY. Al2O3(s) + 2NaOH(aq) + 3H2O(l) ---------> 2NaAl(OH)4(aq)

Select one: a. XYZ only b. XYZ and ZXY c. ZXY and YZX d. YZX only

Determine if the transformation is an Oxidation, Reduction or Neither : Carbon, CO32-→ CO2 Select one: a. Neither b. Reduction c. Oxidation

Determine if the transformation is an Oxidation, Reduction or Neither : Hydrogen, H2O → H2 Select one: a. Neither b. Oxidation c. Reduction Please mark the correct answer If the Ka of acetic acid is 1.8x10-5 and the pH of the buffer is 5.50, what are the concentrations of acetic acid and acetate? Select one: a. Acetate b. 5.75M c. None of the above d. All of the above e. 1.00M f. Acetic acid

Please mark the correct answer What will be the pH of the total solution if a 25.00-mL of 0.200 M HCl solution is added with 12.55-mL 0.200 M NaOH? Select one: a. pH = 2.15 b. pH = 3.25 c. pH = 2.17 d. pH = 1.32

Please mark the correct answer Which of the following has the correct pattern depicting acid strength? Select one: a. HI HClO3> HClO4 d. HCl> HF > HI >HBr

Please mark the correct answer At 25°C, in an acidic condition, Kw will always be __________ 1.0×10-14.

Select one: a. Less than b. Equal c. Greater than

Please mark the correct answer Identify the correct pairing between the conjugate bases and acids. Select one: a. H2C6H6O6 + H2O --------> C6H6O6- + H3O+ b. CH3COOH + H2O -------> CH2COO- + H3O+ c. H2CO3 + H2O

--------> CO3- + H3O+

d. H3C6H5O7 + H2O --------> H2C6H5O7- + H3O+

Determine if the transformation is an Oxidation, Reduction or Neither : Chlorine, Cl2 → ClO4Select one: a. Oxidation b. Reduction c. Neither