Question

Calculate the molarity of h2 s o4 in which mole fraction is 0.85

Answer 1

Answer:Molality of H2SO4=?

n1= number of moles of H2O and n2= number of moles of H2SO4 .

Molality of H2SO4 means the number of moles of H2SO4 present in 1000g of water

g.mol wt of water (H2O)=2×1)+16=18g

Mole fraction of H2O in solution =0.85

Mole fraction of H2SO4 in solution =1−0.85=0.15

n1 = no of moles of H2O

=wt.of.H2Og.mol.wt.ofH2O

=100018

=55.55

n2 = no of moles of H2SO4=?

Mole fraction of H2SO4=n2n1+n2

0.15=n255.55+n2

or 0.15(55.55+n2)=n2

or n20.15n2+8.3325

n2=9.8

Molality =9.8 m

or Molality of H2SO4=xH2SO4xH2O×1Mol.wt.ofH2O×1000

=1−0.850.85

0.15×118×1000=9.8m

Explanation: