Question

From Raoult's law, ethanol+cyclohexane mixture will give a:

• A. positive deviation
• B. negative deviation
• C. no deviation
• D. none of the above

Answer 1

The correct option is A positive deviation

$\text{Explanation}$

$\cdot$ A mixture of cyclohexane and ethanol shows positive deviation from Roult’s law.

$\cdot$ In ethanol there is hydrogen bonding while in cyclohexane there is weak van der Waal 's forces of attraction.

$\cdot$ When they are mixed the hydrogen bonding of ethanol is disturbed as cyclohexane molecules are placed in between ethanol molecules.

$\cdot$ There is no possible bonding between ethanol and cyclohexane molecules but only weak van der Waals' forces exist so the molecules in the mixture have higher tendency to escape.

$\cdot$ This reduce the boiling point of solution.

$\text{Hence the correct option is A}$