Question

8. The boiling point of C6H6, CH3OH, C6H5NH2 and C6H5NO2 are 80°C, 65°C, 184 °C and 212°C
ectively. Which will show highest vapour pressure at room temperature-
(A) C6H6
(B) CH3OH
(C) C6H5NH2 (D) C6H5NO2​

Answer 1

Answer:

CH3OH

Explanation:

It has low boiling point.

Answer 2

Given that,

Boiling point of $C_{6}H_{6}$ =80°C

Boiling point of $CH_{3}OH$ =65°C

Boiling point of $C_{6}H_{5}NH_{2}$ = 184°C

Boiling point of $C_{6}H_{5}NO_{2}$ =212°C

Vapour pressure :

When the pressure exerted by the vapours of a liquid on its surface when they are in equilibrium at a constant temperature.

It is called vapour pressure.

If liquids with high vapor pressures have lower boiling points.

We need to find the compound which shows the highest vapour pressure

Using given data

$CH_{3}OH$ have a lower boiling point.

So, we can say that $CH_{3}OH$ have highest vapour pressure.

$C_{6}H_{5}NO_{2}$ have a highest boiling point.

So, we can say that $C_{6}H_{5}NO_{2}$ have low vapour pressure.

Hence, $CH_{3}OH$ have highest vapour pressure.

(B) is correct option.