Question

what is the boiling point of a solution containing 0.144 g of eugenol dissolved in 10.0 g of benzene

Answer 1

Answer: The boiling point of solution is 80.32°C

Explanation:

To calculate the molality of solution, we use the equation:

$\text{Molality of the solution}=\frac{m_{solute}\times 1000}{M_{solute}\times W_{solvent}\text{ in grams}}$

Where,

$m_{solute}$ = Given mass of solute (eugenol) = 0.144 g

$M_{solute}$ = Molar mass of solute (eugenol) = 164.2 g/mol

$W_{solvent}$ = Mass of solvent (benzene) = 10.0 g

Putting values in above equation, we get:

$\text{Molality of eugenol}=\frac{0.144\times 1000}{164.2\times 10.0}\\\\\text{Molality of eugenol}=0.088m$

To calculate the elevation in boiling point, we use the equation:

$\Delta T_b=iK_bm$

where,

$\Delta T_b$ = elevation in boiling point = $\text{Boiling point of solution}-\text{Boiling point of pure solution}$

Boiling point of pure solution (benzene) = 80.1°C

i = Vant hoff factor = 1 (For non-electrolytes)

$K_b$ = molal boiling point elevation constant = 2.53°C/m

m = molality of solute = 0.088 m

Putting values in above equation, we get:

$\text{Boiling point of solution}-80.1=1\times 2.53^oC/m\times 0.088m\\\\\text{Boiling point of solution}=0.22+80.1=80.32^oC$

Hence, the boiling point of solution is 80.32°C