Question

A 544 mg of a mixture of fluorene and benzoic acid was weighed out and subjected to an extraction and recrystallization. After this purification was completed the product crystals were dried and analyzed. The purification procedure produced 1.80 × 102 mg of fluorene and 196 mg of benzoic acid. Calculate the percent composition of this mixture.

Answer 1

Answer: The percent composition of fluorene is 33.08 % and benzoic acid is 36.03 %.

Explanation:

We are given:

Mass of mixture = 544 mg

Mass of fluorene after purification = $1.80\times 10^2mg=180mg$

Mass of benzoic acid after purification = 196 mg

To calculate the percentage composition of a substance in a mixture, we use the equation:

$\%\text{ composition of substance}=\frac{\text{Mass of substance}}{\text{Mass of mixture}}\times 100$

For fluorene:

$\%\text{ composition of fluorene}=\frac{180}{544}\times 100=33.08\%$

Hence, the percent composition of fluorene is 33.08 %

For benzoic acid:

$\%\text{ composition of benzoic acid}=\frac{196}{544}\times 100=36.03\%$

Hence, the percent composition of benzoic acid is 36.03 %