Question

the boiling point of benzene is 353.2k.when 1.8 of a non-volatile solute was dissolved in 90g benzene the boiling point was raised to 354.1 k. calculate the molecular mass of the solute. (kb of benzene =2.53 k kg mol-1)​

Answer 1

Answer:57.5 g/mol

Explanation:

Answer

a) The elevation in the boiling point ΔT  

b

​  

=354.11−353.23=0.88 K.

The expression for the molar mass of the solute is

M  

2

​  

=  

ΔT  

b

​  

×w  

1

​  

 

K  

b

​  

×w  

2

​  

×1000

​  

 

Substitute values in the above expression.

M  

2

​  

=  

0.88×90

2.53×1.8×1000

​  

=57.5 g/mol

Hence, the molar mass of the solute is 57.5 g/mol