the density of 1molar solution of H2SO4 is 1.298g/ml ? calculate the m

1.	the density of 1molar solution of H2SO4 is 1.298g/ml ? calculate the molality of solution ?
Answer» Molality ofH2SO4=?H2SO4=? n1n1= number of moles ofH2OH2Oandn2n2= number of moles ofH2SO4H2SO4. Molality ofH2SO4H2SO4means the number of moles ofH2SO4H2SO4present in1000g1000gof water g.mol wt of water(H2O)=2×1)+16=18g(H2O)=2×1)+16=18g Mole fraction ofH2OH2Oin solution=0.85=0.85 Mole fraction ofH2SO4H2SO4in solution=1−0.85=0.15=1−0.85=0.15 n1n1= no of moles ofH2OH2O =wt.of.H2Og.mol.wt.ofH2O=wt.of.H2Og.mol.wt.ofH2O =100018=100018 =55.55=55.55 n2n2= no of moles ofH2SO4=?H2SO4=? Mole fraction ofH2SO4=n2n1+n2H2SO4=n2n1+n2 0.15=n255.55+n20.15=n255.55+n2 or0.15(55.55+n2)=n20.15(55.55+n2)=n2 orn20.15n2+8.3325n20.15n2+8.3325 n2=9.8n2=9.8 Molality =9.8 m or Molality ofH2SO4=xH2SO4xH2O×1Mol.wt.ofH2OH2SO4=xH2SO4xH2O×1Mol.wt.ofH2O×1000×1000 =1−0.850.85=1−0.850.85 0.15×118×0.15×118×10001000=9.8m actually it not too long for class 11 student ...I can't understand this properly

the density of 1molar solution of H2SO4 is 1.298g/ml ? calculate the molality of solution ?

Answer»

Molality ofH2SO4=?H2SO4=?

n1n1= number of moles ofH2OH2Oandn2n2= number of moles ofH2SO4H2SO4.

Molality ofH2SO4H2SO4means the number of moles ofH2SO4H2SO4present in1000g1000gof water

g.mol wt of water(H2O)=2×1)+16=18g(H2O)=2×1)+16=18g

Mole fraction ofH2OH2Oin solution=0.85=0.85

Mole fraction ofH2SO4H2SO4in solution=1−0.85=0.15=1−0.85=0.15

n1n1= no of moles ofH2OH2O

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

=100018=100018

=55.55=55.55

n2n2= no of moles ofH2SO4=?H2SO4=?

Mole fraction ofH2SO4=n2n1+n2H2SO4=n2n1+n2

0.15=n255.55+n20.15=n255.55+n2

or0.15(55.55+n2)=n20.15(55.55+n2)=n2

orn20.15n2+8.3325n20.15n2+8.3325

n2=9.8n2=9.8

Molality =9.8 m

or Molality ofH2SO4=xH2SO4xH2O×1Mol.wt.ofH2OH2SO4=xH2SO4xH2O×1Mol.wt.ofH2O×1000×1000

=1−0.850.85=1−0.850.85

0.15×118×0.15×118×10001000=9.8m

actually it not too long for class 11 student ...I can't understand this properly