Chemistry IJSO Stage-1

IJSO STAGE-I DAILY PRACTICE PROBLEMS SESSION-2012-13 DPP : 01

SUBJECT : CHEMISTRY

TOPIC : MOLE CONCEPT I 1.

The total number of protons in 10g of calcium carbonate is (NO = 6.023 × 1023) (A) 1.5057 × 10 24 (B) 2.0478 × 1023 (C) 3.0115 × 1024 (D) 4.0956 × 1024

2.

Which of the following has the highest mass ? (A) 1g atom of C (C) 10 ml of water

1 mol of CH4 2 (D)3.011×1023 atoms of oxygen (B)

3.

12  of H2 and 11.2  of Cl2 are mixed and exploded. The composition by volume of mixture is (A) 24  of HCl (g) (B) 0.8  Cl2 and 20.8  HCl(g) (C) 0.8  H2 and 22.4  HCl(g) (D) 22.4  HCl(g)

4.

Copper metal reacts with nitric acid, according to the reaction 3Cu(s) + 8HNO3(aq)  3Cu(NO3)2(aq) + 2NO(g) + 4H2O() If 18.75 g Cu(NO3)2 is eventually obtained, then how many grams of nitric oxide, would have also formed according to the preceeding equation ? (A) 2g (B) 4g (C) 6g (D) 8g

5.

A spherical ball of radius 10 cm contains 56% iron. If density is 1.2 g/cm3 , number of mol of Fe present approximately is (A) 24 (B) 20 (C) 50 (D) 25

6.

On heating O3 its volume : (A) remains unchanged

7.

8.

(B) becomes doubled 3 (C) becomes half (D) becomes times 2 Number of water molecules in the drop of water, if 1 ml of water has 20 drops and A is Avogadro’s number is (A) 0.5 A/18 (B) 0.05 A (C) 0.5 A (D) 0.05A/18 N2 + 3H2  2NH3, molecular weight of NH3 and N2 are x1 and x2, their equivalent weight are y1 and y2. Then (y1 – y2) is -

2 x1 – x 2 (B) x1 – x2 (C) 3x1 – x2 (D) x1 – 3x2 6 Read the following passage carefully and answer the questions given after the passage. Milk of sulphur is soluble in CS2 and mainly used in medicine. A doctor wants to produce 6.4 kg milk of sulphur , so he went to laboratory and took milk of lime [Ca(OH)2] with sulphur and again decomposing the products formed with HCl, milk of sulphur i.e. , white sulphur is formed. Reaction involving in the production of white sulphur are (A)

2CaS5 + CaS2O3 + 6HCl 9.

Doctor wants to produce (A) 1. 2046 × 1026 sulphur atom (C) 6.023 × 1023 sulphur atom

3CaCl2 + 3H2O + 12S  (white) (B) 1.2046 × 1023 white sulphur atom (D) 1. 2046 × 1026 white sulphur atom

10.

How many mole of Ca(OH)2 is used for the production of 6.4 kg of milk of sulphur ? (A) 0.50 mole (B) 0.80 mole (C) 50 mole (D) 80 mole

11.

How many mole of HCl is used in this process ? (A) 100 mole (B) 200 mole (C) 10 mole

12.

(D) 20 mole

When milk of lime is reacted with sulphur, the oxidation state of sulphur changes from zero to (A) –2/5 (B) –2/5 and +2 (C) +2 (D) +2 and +4

IJSO STAGE-I DAILY PRACTICE PROBLEMS SESSION-2012-13 DPP : 02

SUBJECT : CHEMISTRY

TOPIC : MOLE CONCEPT II & ACIDS, BASES AND SALTS 1.

What volume of a solution of hydrochloric acid containing 73g of acid per litre would sufficient for the exact neutralization of sodium hydroxide obtained by allowing 0.46 g of metallic sodium to act upon water ? (A) 20 m (B) 15 m (C) 10 m (D) 25 m

2.

What volume of 0.1 M H2SO4 must be added to 50 ml of a 0.1 M NaOH solution to make a solution in which the molarity of the H2SO4 is 0.050 M ? (A) 400 m (B) 50 ml (C)100 m (D) 150 m

3.

The density (in g m–1) of a 3.60 M sulphuric acid solution that is 29% by mass will be (A) 1.22 (B) 1.45 (C) 1.64 (D) 1.88

4.

2g sample containing Na2CO3 and NaHCO3 loses 0.248 g when heated to 300ºC, the temperature at which NaHCO3 decomposes to Na2CO3 and H2O. What is the % of Na2CO3 in the mixture ? (A) 33.6% (B) 67.4% (C) 67.2% (D) 32.8%

5.

In which of the following term mass of solvent is used ? (A) Molarity (B) Molality (C) Solubility

(D) Both (B) and (C)

6.

300 ml of 3M NaCl is added to 200 ml of 4M BaCl2 solution. The concentration of Cl– ions in the resulting solution is (A) 7 M (B) 1.6 M (C) 1.8 M (D) 5 M

7.

The volume of water to be added to 100 cm3 of 0.5 N H2SO4 to get deci normal concentration is : (A) 100 cm3 (B) 450 cm3 (C) 500 cm3 (D) 400 cm3

8.

Salt solution of sodium bicarbonate is (A) Basic (C) Neutral

9.

(B) Acidic (D) Depends on concentration

Which of the following will released hydrogen when reacts with sodium ? (A) HCl (B) C2H5OH (C) C2H2

(D) All of these

10.

pH of a solution prepared by mixing 25 ml of 0.05 M solution of HCl, 10 mL of 0.5 NaOH, 50 mL of 0.05 M solution of H2SO4 and 15 ml of water will be (A) 12.903 (B) 1.903 (C) 12.097 (D) 1.097

11.

The pH of a solution of 0.1 M CH3COOH increases when which of the following substance is added ? (A) NaHSO4 (B) HClO4 (C) NH4NO3 (D) K2CO3

12.

10–5 M NaOH solution at 25ºC is diluted 1000 times. The pH of the solution will (A) be equal to 8 (B) lie between 7 and 8 (C) lie between 6 and 7 (D) remain unchanged

13.

The number of H+ ions present in 1 ml of a solution having pH = 13 is (A) 1013 (B) 6.023 × 1013 (C) 6.023 × 107

(D) 6.023 × 1010

14.

The pH of aqueous solutions of three acids A, B and C respectively is 3, 2 and 1. What will be the ratio of their [H+] ? (A) 1 : 2 : 3 (B) 300 : 200 : 10 (C) 100 : 10 : 1 (D) 1 : 10 : 100

15

10 mL of 0.1 N HCl is added to 990 mL solution of NaCl. The pH of the resulting solution is(A) zero (B) 3 (C) 7 (D) 10

IJSO STAGE-I DAILY PRACTICE PROBLEMS SESSION-2012-13 DPP : 03

SUBJECT : CHEMISTRY

TOPIC : METALS AND NON-METALS 1.

2.

Slag is usually (A) lighter than molten metal.

(B) heavier than molten metal.

(C) mixed with molten metal.

(D) a form of silica.

Fluorspar and feldspar respectively are (A) KAlSi3O8,CaF2

3.

4.

(B) CaF2, Fe2O3

(C) CaF2 , KAlSi3O8

(D) Fe2O3, CaF2

The function of flux during the smelting of the ore is (A) to make the ore porous

(B) to remove gangue

(C) to facilitate reduction

(D) to facilitate oxidation

Which method of purification is represented by the following equations ? 1700 K 523 K Ti + I4   Ti + 2 I2  TiI4  

(A) zone refining 5.

6.

7.

(B) Mond’s process

(C) leaching

(D) Van Arkel process.

The incorrect statement is (A) Calamine and siderite are carbonates

(B) Argentite and cuprite are oxides.

(C) Zinc blende and iron pyrites are sulphides

(D) Malachite and azurite are ores of copper.

Aluminium oxide reacts with sodium hydroxide to form (A) Sodium meta aluminate and hydrogen

(B) Sodium meta aluminate and water

(C) Aluminium hydroxide and sodium oxide.

(D) Sodium -aluminium alloy and water.

Which method of purification is represented by the following equation ? 70 º C 180 º C Ni + 4CO   Ni(CO)4    Ni + 4CO

(A) Van Arkel 8.

9.

(B) Mond’s process

(C) Zone refining

(D) Liquation

In the commercial electro chemical process for aluminium extraction, the electrolyte used is (A) Al(OH)3 in NaOH solution

(B) An aqueous solution of Al2(SO4)3

(C) A molten mixture of Al2O3 and Na3AlF6

(D) A molten mixture of Al2O3 and Al(OH)3

Leaching of silver from argentite is done by Mac-Arthur forest cyanide process which involves following reaction. Ag2S + NaCN  [A] [A] + Zn  [B] [B] is a metal . Hence [A] and [B] are (A) Na2[Zn(CN)4], Zn

10.

(B) Na[Ag(CN)2], Ag

(C) Na2[Ag(CN)4], Ag

(D) Na3[Ag(CN)4], Ag

(A) 2CuCO3. Cu(HCO3)2 (B) CuCO3.2Cu(OH)2

(C) 2CuCO3. Cu(OH)2

(D) Cu(HCO3)2. Cu(OH)2

Azurite is -

IJSO STAGE-I DAILY PRACTICE PROBLEMS SESSION-2012-13 SUBJECT : CHEMISTRY

DPP : 04

TOPIC : STRUCTURE OF ATOM 1.

Which is the correct statement about a proton ? (A) It is nucleus of deuterium. (B) It is ionised hydrogen molecule. (C) It is ionised hydrogen atom. (D) It is alpha particle.

2.

Match List-I with List-II and select the correct answer using the codes given below the lists ( and m are respectively the azimuthai and magnetic quantum no.) List-I List-II (A) Number of value of  for an energy level (1) 0, 1, 2, ............. (n - 1) (B) Value of  for a particular type of orbital (2) + to – through zero (C) Number of values of m for  = 2 (3) 5 (D) Value of 'm' for a particular type of orbitals (4) n

3.

The atoms of various isotopes of a particular element differ from each other in the number of (A) electron in the outer shell only (B) protons in the nucleus (C) electrons in the inner shells only (D) neutrons in the nucleus

4.

An electron in an atom (A) moves randomly around the nucleus. (B) has fixed space around nucleus. (C) is stationary in various energy levels. (D) moves around its nucleus in definite energy levels.

5.

S1 : Bohr model is applicable for Be2+ ion. S2 : Total energy coming out of any light source is integral multiple of energy of one photon. S3 : Number of waves present in unit length is wave number. S4 : q/m ratio in cathode ray experiment is independent of the nature of the gas. (A) F F T T (B) T T F F (C) F T T T (D) T F F F

6.

Choose the correct statement among the following (A) Thomson atomic model is also known as plum-pudding model. (B) Rutherford atomic model led to the discovery of the nucleus. (C) According to Bohr’s atomic model , electrons revolve around the nucleus in well defined orbits. (D) All statements are correct.

7.

Atomic number (i) is denoted by ‘Z’. (ii) is no. of protons in an atom. (iii) is no. of electrons in charged atom. (iv) is equal to sum of protons and neutrons in an atom. Correct statement is (A) (i) to (iv) all (B) (i) and (ii) only (C) (ii) and (iv) only

8.

(D) (iii) and (iv) only

For the energy levels in an atom which one of the following statement is correct ? (A) The 4s sub-energy level is at a higher energy than the 3d sub-energy level. (B) The M- energy level can have maximum of 32 electrons. (C) The second principal energy level can have four orbitals and contain a maximum of 8 electrons. (D) The 5th main energy level can have maximum of 50 electrons.

9.

10.

The order of increasing energies of the orbitals follows (A) 3s, 3p, 4s, 3d, 4p

(B) 3s, 3p, 3d, 4s, 4p

(C) 3s, 3p, 4s, 4p, 3d

(D) 3s, 3p, 3d, 4p, 4s

The number of electrons in an atom with atomic number 105 having ( n+ )=8 is (A) 15

11.

(B) 17

(C) 19

(D) 21

In Cu ( Atomic no. 29 ) (A) 13 electrons have spin in one direction and 16 electrons in other direction. (B) 14 electrons have spin one direction and 15 electrons in other direction. (C) one electron can have spin only in the clockwise direction. (D) none of the above is correct.

12.

Consider the ground state of Cr atom.The number of electrons with the azumithal quantum numbers = 1 and 2 are respectively(A) 12 and 4

(B) 12 and 5

(C) 16 and 4

(D) 16 and 5

IJSO STAGE-I DAILY PRACTICE PROBLEMS SESSION-2012-13 05

SUBJECT : CHEMISTRY

DPP :

TOPIC : PERIODIC TABLE 1.

Without looking at the periodic table, select the elements of IIIA group of the periodic table (atomic numbers are given) : (A) 3, 11, 19, 37 (B) 5, 13, 21, 39 (C) 7, 15, 31, 49 (D) 5, 13, 31, 49

2.

Which pair is different from the others : (A) Li – Mg (B) B – Si

(C) Be – Al

(D) Li – Na

3.

Which of the following series of elements have nearly the same atomic radii ? (A) F, Cl, Br, I (B) Na, K, Rb, Cs (C) Li, Be, B, C (D) Fe, Co, Ni, Cu

4.

The elements having highest ionization enthalpies within their periods are called (A) halogens (B) noble gases (C) alkali metals (D) transition elements

5.

The correct order of size among Cl, Cl+ and Cl– is (A) Cl+ < Cl– < Cl (B) Cl+ > Cl– > Cl (C) Cl+ < Cl < Cl–

(D) Cl– < Cl < Cl+

Which of the following properties generally decreases along a period ? (A) Ionisation energy (B) Atomic radii (C) Electron affinity

(D) Valency

The correct order of increasing atomic radius of the following elements is (A) S < O < Se < C (B) O < C < S < Se (C) O < S < Se < C

(D) C < O < S < Se

6.

7.

8.

The electron affinities of halogens are : F = – 332, Cl = – 349, Br = – 324, I = – 295 kJ mol–1 The higher value of Cl as compared to that of F is due to : (A) higher atomic radius of F (B) smaller electronegativity of F (C) weaker electron repulsion in Cl (D) more vacant p-subshell in Cl

9.

In the modern periodic table which one of the following does not have appropriate position ? (A) Inert gases (B) Inner-transition elements (C) Transition elements (D) Fluorine

10.

Element of which of the following atomic nos. has lowest EN? (A) 37 (B) 55 (C) 87

11

12.

(D) 105

Match the following : Column-I

Column-II

(element / elements)

(group number)

(A) (B)

An element whose fourth shell contains two p-electrons An element whose valence shell contains one unpaired p-electron

(p) 8th group (q) 12th group

(C)

An element which receives last electron in (n – 1) d-subshell

(r) 14th group

(D)

An element with the ground-state electron configurationa[Ar]4s23d10

(s) 17th group

Arrange the following in increasing radii (a) Li+, Na+, K+ (c) Mg, Mg+, Mg2+ (e) O, O–, O2– (g) Na+, Ne

(b) K+, Ca2+, Ar (d) O2–, N3–, F– (f) Mg2+, Ca2+ (h) P3–, N3–

IJSO STAGE-I DAILY PRACTICE PROBLEMS SESSION-2012-13 SUBJECT : CHEMISTRY

DPP : 06

TOPIC : NUCLEAR CHEMISTRY 1.

2.

3.

Radioactivity is due to (A) stable electronic configuration

(B) unstable electronic configuration

(C) stable nucleus

(D) unstable nucleus

-rays have ionisation power because they possess (A) lesser kinetic energy

(B) higher kinetic energy

(C) lesser penetration power

(D) higher penetration power

A magnet will cause greatest deflection of (A) -rays

4.

(B) -rays

(B)  >  > 

7.

(B) -rays

(D)  >  > 

(C) - rays

(D) All have equal effect

In -decay n/p ratio (A) may increase or decrease

(B) remains constant

(C) decreases

(D) increases

238 92 U

emits an alpha particle, the product has mass number and atomic number -

(A) 236, 92 8.

(C)  >  > 

Which of the following radiation have least effect on both the photographic plate and zinc sulphide screen ? (A) -rays

6.

(D) neutrons

The ionising power of ,  and  rays is in the decreasing order (A)  >  > 

5.

(C) -rays

The isotope

(B) 234,90 235 92 U

(C) 238, 90

decays in a number of steps to an isotope of

(D) 236, 90 207 82 Pb

. The groups of particles emitted in

this process will be (A) 4 , 7 

9.

When

226 88 Ra emits

(A) third group

10.

The

238 92 U

(A) 92

(B) 6, 4

(C) 7, 4

(D) 10, 1

an -particle , the new element formed belongs to (B) zero group

(C) fourth group

(D) second group

disintegrates to give 4 and 6 particles. The atomic no. of the end product is (B) 96

(C) 84

(D) 90

CHEMISTRY _IJSO STAGE-IDPP-1 Ques Ans

1 C

2 A

3 C

4 A

5 C

6 D

7 D

8 A

9 D

10 C

11 A

12 B

CHEMISTRY _IJSO STAGE-IDPP-2 Ques Ans

1 C

2 C

3 A

4 B

5 D

6 D

7 D

8 A

9 D

10 B

11 D

12 B

13 C

CHEMISTRY _IJSO STAGE-IDPP-3 Ques Ans

1 A

2 C

3 B

4 D

5 B

6 B

7 B

8 C

9 B

10 C

CHEMISTRY _IJSO STAGE-IDPP-4 Ques Ans

1 C

2

3 D

4 D

5 C

6 D

7 B

8 C

9 A

10 B

11 B

2. (A)-(4), (B)-(1), (C)-(3), (D)-(2)

CHEMISTRY _IJSO STAGE-IDPP-5 Ques Ans

1 D

2 D

3 D

4 B

5 C

6 B

7 B

8 C

9 B

10 B

CHEMISTRY _IJSO STAGE-IDPP-6 Ques Ans

1 D

2 B

3 B

4 A

5 C

6 D

7 B

8 C

9 B

10 D

12 B

14 D

15 B