Question

You are given the following boiling point data. Which of the liquids would you expect to have the highest vapor pressure at room temperature?Ethanol, C2H5OH 78.5 °CEthylene glycol, C2H4(OH)2 198.0 °CDiethyl ether, C3H10O2 34.5 °CWater, H2O 100.0 °CMethanol, CH3OH 64.96 °C

Answer 1

Answer:

Diethyl ether

Explanation:

vapor pressure - the pressure exerted by the gaseous molecules on the walls of the container , is called its vapor pressure.

The compound with higher boiling point , will have lower vapor pressure ,

and the compound with lower boiling point , will have higher vapor pressure.

Hence, Boiling point and vapor pressure have inverse relation.

The vapor pressure and boiling point both, depends on the inter molecular interactions , i,e, the interaction between the molecules.  

Since, the compound with stronger inter molecular interactions, will not easily convert to gas, hence will have higher boiling point between , therefore , its vapor pressure would be less.

But the compound with less inter molecular interactions , can easily vaporize to convert to gaseous state and hence will have lower boiling point, therefore, its vapor pressure would be higher .

Among all the options , diethyl ether have lowest boiling point , hence, will have highest vapor pressure , at room temperature.