Question

the amount of urea to be dissolved in 500ml of water to produce a depression of 0.186c in freezing point​

Answer 1

Answer: 3 grams

Explanation:

Depression in freezing point is given by ;

$\Delta T_f=i\times k_f\times m$

$\Delta T_f=T_f^0-T_f$ =  Depression in freezing point

$k_f$ = molal freezing point constant

m = molality

$\Delta T_f=i\times k_f\times \frac{\text{mass of solute}}{\text{molar mass of solute}\times \text{weight of solvent in kg}}$

For urea, i= 1 as it is a non electrolyte and does not dissociate.

weight of water =$density\times volume=1g/ml\times 500ml=500g=0.5 kg$

$0.186^0C=1\times 1.86\times \frac{x}{60\times 0.5kg}$

$x=3g$

Thus the amount of urea to be dissolved is 3 grams.

Read more on Brainly.in - https://brainly.in/question/10277751#readmore