Question

Calculate the freezing point of a solution containing 8.1 g of hbr in 100 g of water assuming the acid to be 90% ionised

Answer 1

The freezing point of the solution will be -3.53⁰C

Explanation:

molar mass of HBr = 81 g

=> number of moles of HBr in 8.1 hm = 8.1/81 = 0.1 moles.

HBr ⇔ H⁺  +  Br⁻

Hence,

i = 1 + (2-1)x0.9 = 1.9

We know that,

ΔT = i x Kf x 1000 x m/w

= 1.9 x 1.86 x 1000 x 0.1/100

= 3.53

=> Freezing point = 0 - 3.53

= -3.53⁰C

Hence freezing point of the solution will be -3.53⁰C

Answer 2

Answer:

refer to the attachment..........