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sing a primary standard to analyze acid and base solutions

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Using a primary standard to analyze acid and base solutions Acid-base titration Lab 13G
Jake Shewchuk Lab 13C Dominique Genereux

Purpose 13G:
1. To prepare a standard solution of oxalic acid and use it to standardize an unknown sodium hydroxide solution.
Purpose 13C:
1. To titrate a hydrochloric acid solution of “unknown” concentration with standardized 0.5M sodium hydroxide.
2. To titrate a hydrochloric acid solution of “known” concentration with standardized 0.5M sodium hydroxide.
3. To titrate an acetic acid solution (vinegar) with standardized 0.5M sodium hydroxide.
4. To utilize the titration results to calculate the molarity of the hydrochloric acid and the …show more content…

% difference= (larger value - smaller value)/ (larger value + smaller value)/2 * 100%
% difference= (.5418M - .5225M)/ (.5418M+ .5225M)/2 * 100%
% difference=.91%

Follow up 13G:
1. The property of this acid solution (soft drink) overcome by using of sugar or artificial sweetener is the sourness. Most acids are sour so the sugar makes it sweeter in a soft drink, so it is more desirable to drink.
2. What mass concentrated HCl will be required required to neutralize the NaOH? NaOH moles n=C*v n=8.0x103L* .040M n=320 mols HCl moles =320 mols HCl volume v=n/C v=320 mols / 12M v=26.66666 HCl mass m=d*v m=1.2Kg/L / 26.66666 m=32Kg or 32000 g 3. Calculating the the percentage by mass of NaCO in the sample:
Moles of HCl n=C*v n=.500M*.0486L n=.0243mols Moles of NaOH n=m/MM n=1.00g/40.0 n=.0250mols 2HCl(aq) + Na2CO3 → 2NaCl(aq) + H2O(l) + CO2(g)
Moles of Na2CO3 n=m/MM n=1.00g/160.0 n= .0094339623moles .0243 (moles of HCl) = x * 0.01887 + (1.000 - x) * .0250 .0243 = .01887x + .0250 - .0250x
.00613x = .0007 x=0.114 Percentage of Na2CO3 by mass is 11%

4. It would be difficult to measure the concentration of acid in red wine or coca-cola because the colour of the drink is too dark for us to see when the phenolphthalein indicator changes colour. You could overcome this difficulty by using a pH meter.

5. Explaining why the conductivity reaches a minimum.
Ionic equation:
Ba2+(aq) + 2OH-(aq) + H+(aq)+ HSO4(aq) → BaSO4(s) + 2HOH(l)

At the neutralization

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