Question

Calculate the boiling point of a solution of 500.0 g of ethylene glycol (c2h6o2) dissolved in 500.0 g of water. kf = 1.86°c/m and kb = 0.512°c/m. use 100°c as the boiling point of water.

Answer 1

Answer:The boiling point of the solution is 108° C.

Explanation:

Boiling point of pure water=T=$100^oC$

Boiling point of water after addition of 500 g of ethylene glycol=$T_f$

Mass of water = 500g = 0.5 kg (1000 g = 1 kg)

$\Delta T_f=K_b\times \frac{\text{Mass of ethlyene glycol}}{\text{Molar mass of ethylene glycol}}$

$\Delta T_f=0.512^oC/m\times \frac{500 g}{62.07 g/mol\times 0.5 kg}$

$\Delta T_f=8.24 ^oC$

$\Delta T_f=T_f-T$

$8.24^oC=T_f-100^oC$

$T_f=108.24^oC$

The boiling point of the solution is 108° C.