Analytical Chemistry Question 188
Question: 1.25 g of a sample of $ Na_2CO_3 $ and $ NaSO_4 $ is dissolved in 250 ml solution. 25 ml of this solution neutralises 20 ml of 0. 1 N $ H_2SO_4 $ . The % of $ Na_2O_2 $ in this sample is
Options:
A) 84.8%
B) 8.48%
C) 15.2%
D) 42.4%
Show Answer
Answer:
Correct Answer: A
Solution:
[a] Let the amount of $ Na_2CO_3 $ present in the mixture be x g. $ Na_2SO_4 $ will not react with $ H_2SO_4 $ . Then $ \frac{x}{53}~=\frac{20\times 0.1\times 10}{1000}\therefore x=1.60g $
$ \therefore $ Percentage of $ Na_2C{O_3} $
$ =\frac{1.06\times 100}{1.25}=84% $ %
BETA
