how is elevation in boiling is helpful in calculating the molar mass of a solute
Answers
Explanation:
Elevation of Boiling Point: Elevation of boiling point on adding one mole solute to 1000 g solvent is called molal boiling point elevation constant. It is denoted by K
b
. Its unit is K kg mol
−1
, e.g. for water K
b
=0.52 K kg mol
−1
.
Derivation of relation: Increase in boiling point of the solvent, on adding non-volatile solute to the solvent is called elevation of boiling point.
ΔT
b
=T
3
−T
2
where T
2
= boiling point of solvent, and T
3
= boiling point of solution.
Experimentally, it is observed that elevation in boiling point is directly proportional to molal concentration of solute dissolved in definite amount of the solvent.
ΔT
b
∝m
ΔT
b
=K
b
×m .....(1)
K
b
is proportionality constant called molal boiling point elevation constant. We know that molality of a solution is number of moles of solute in 1000g solvent. It is denoted by m.
Determination of Molecular mass of a non-volatile solute:
Say molecular mass of the solute is M
1
. W
1
g solute is present in W
2
g solvent. Molality of solution is
m=
M
1
W
1
×
W
2
1000
.........(2)
On putting value of m from equation (2) to (1),
ΔT
b
=
M
1
×W
2
K
b
×W
1
×1000
M
1
=
ΔT
b
×W
2
K
b
×W
1
×1000
Molecular mass of the solute may be determined by this formula
here's ur answer dude
Elevation of Boiling Point: Elevation of boiling point on adding one mole solute to 1000 g solvent is called molal boiling point elevation constant. It is denoted by K
b
. Its unit is K kg mol
−1
, e.g. for water K
b
=0.52 K kg mol
−1
.
Derivation of relation: Increase in boiling point of the solvent, on adding non-volatile solute to the solvent is called elevation of boiling point.
ΔT
b
=T
3
−T
2
where T
2
= boiling point of solvent, and T
3
= boiling point of solution.
Experimentally, it is observed that elevation in boiling point is directly proportional to molal concentration of solute dissolved in definite amount of the solvent.
ΔT
b
∝m
ΔT
b
=K
b
×m .....(1)
K
b
is proportionality constant called molal boiling point elevation constant. We know that molality of a solution is number of moles of solute in 1000g solvent. It is denoted by m.
Determination of Molecular mass of a non-volatile solute:
Say molecular mass of the solute is M
1
. W
1
g solute is present in W
2
g solvent. Molality of solution is
m=
M
1
W
1
×
W
2
1000
.........(2)
On putting value of m from equation (2) to (1),
ΔT
b
=
M
1
×W
2
K
b
×W
1
×1000
M
1
=
ΔT
b
×W
2
K
b
×W
1
×1000
Molecular mass of the solute may be determined by this formula.
Maybe it's help u