Question

What mass of solid that has a molar mass of 46.0 g/mol should be added to 150.0 g of benzene to raise the boiling point of benzene by 6.28°C? (The boiling point elevation constant of benzene is 2.53°C•kg/mol.) Use mc029-1.jpg. 2.48 g 8.25 g 17.1 g 43.3 g

Answer 1

Answer : 17.12 g

Step-by-step explanation:
`\Delta T =k_b* m`

`\Delta T` = elevation in boiling point

`k_b` = boiling point elevation constant

m= molality

`molality=(mass of solute)/(molecular mass of solute* weight of the solvent in kg)`

given
`\Delta T=6.28^(\circ)C`

Molar mass of solute = 46.0
`gmol^(-1)`

Weight of the solvent = 150.0 g = 0.15 kg

Putting in the values

`molality=(x)/(46gmol^(-1)*0.15kg)`

`6.28 =2.53^(\circ)Ckgmol^(-1)(x)/(46gmol^(-1)* 0.15kg)`

x = 17.12 g