Analysis of Commercial Bleach Lab

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   Pre-Lab Questions 1.| What is meant by a ͞titration͟? #   !   !%   &            !%   & 2.|  solution of household vinegar (a mixture of acetic acid and water) is to be analyzed.  pipet is used to measure out 10.0 mL of the vinegar, which is placed in a 250mL volumetric flask. Distilled water is added until the total volume of solution is 250 mL.  25.0-mL portion of the diluted solution is measured out with a pipet and titrated with a standard solution of sodium hydroxide. The neutralization reaction is as follows: HC2H3O2(aq) + OH-(aq) ї C2H3O2-(aq) + H2O(l) It is found that 16.7 mL of 0.0500 M NaOH is needed to titrate 25.0 mL of the diluted vinegar. Calculate the molarity of the diluted vinegar. r 'r() r'r ) %*+**r, -c&%./0&'%r  1" &%2+*& r  1" '*334r  1"  3.| Calculate the molarity of the household vinegar. r 'r() r'r ) %*334r  1" &%2+*  1" &'%r   1" &%.** c  1" & r   1" '%*334r  1" 2+*  1" &(.** c  )"  r   1" '53+r  å.| The household vinegar has a density of 1.05g/mL. Calculate the percent by mass of acetic acid in the household vinegar.

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:    Calculations 1.| Determine the number of moles of sodium thiosulfate that are equivalent to one mole of sodium hypochlorite. . -$%.2(. -$&%.3$(.2&%2†2-32$(.3$&'2 †2-32$# . -$'2†2-32$ 2.| Calculate the average volume of Na2S2O3 needed for the titration of 25.0 mL of diluted bleach. .6;.0;.6'++(3'.533 3.| âse the average volume and molarity of Na2S2O3 to determine the molarity of the diluted bleach. %.**r, 2†2-3&%*.53, 2†2-3&'2%