Solutions Question 393
Question: Find the molality of $ H_2SO_4 $ solution whose specific gravity is $ 1.98,g,m{l^{-}} $ and 95% of volume is $ H_2SO_4 $ .
Options:
A) 7.412
B) 8.412
C) 9.412
D) 10.412
Show Answer
Answer:
Correct Answer: C
Solution:
$ H_2SO_4 $ is 95% by volume, so wt. of $ H_2SO_4=95,g $ Vol. of solution = 100 ml
$ \therefore $ Moles of $ H_2SO_4=\frac{95}{98}. $
And weight of solution $ =100\times 1.98=198g $
Weight of water $ =198-95=103g $
Molality $ =\frac{95\times 1000}{98\times 103}=9.412 $
Hence, molality of $ H_2SO_4 $ solution is 9.412.