Question

The molality of solution containing 15.20 g of urea, (molar mass = 60) dissolved in 150 g or water is ______.

Options

• 1.689 mol kg^-1 

• 0.1689 mol kg^-1 

• 0.5922 mol kg^-1 

• 0.2533 mol kg^-1

Answer 1

The molality of solution containing 15.20 g of urea, (molar mass = 60) dissolved in 150 g or water is 0.1689 mol kg^-1.

Explanation:

Molality (m) = `"Number of moles of solute"/"Mass of solvent (in kg)"`

`=> (15.2/60)/0.150`

`=> 0.2533/0.115`

= 1.689 mol kg^-1