Question

(a) What is the molality of 46% by mass of aqueous solution of HCOOH acid?

(b) Calculate the mole fraction of HCOOH in above solution.

Answer 1

Answer:

46%by mass of aquous solution means 46gm hcooh and 54gm of water

now molality is no of moles per kg of sol

no of moles -given weight/molar mass

46/46=1

molality- 1000×1/54

mole fraction-... moles of HCOOH is 1

moles of h2o - 54/18=3moles

now mole fraction of hcooh=moles of HCOOH/total moles - 1/(3+1)=0.25