Question

Use the following vapor pressure data to answer the questions:

Liquid Vapor Pressure, torr Temperature, °C

A) C3H7OH 400torr, 82.0 C

B) C2H5SH 400torr ,17.7 C

(1) In which liquid are the intermolecular attractive forces the strongest ? (A or B?)

(2) Which liquid would be expected to have the highest vapor pressure at 49.9 °C? (A or B?)

Answer 1

1)

Given date shown both A and B have same pressure but temperature is more in A.

So, A has stronger intermolecular force because it requires larger increase in temperature to have same vapour pressure

Answer: A

2)

Since B has weaker intermolecular force, B will be vapourised more easily.

Hence B will have greater vapour pressure

Answer: B