Question

A 5.325-gram sample of methyl benzoate, a compound used in the manufacture of perfumes, is found to contain 3.758 g carbon, .316 g hydrogen, and 1.251 grams of oxygen. What is the empirical formula for this substance?

Answer 1

The empirical formula for the compound is C₄H₄O₁

Step-by-step explanation

Given:

Mass composition: 3.758 g carbon, 0.316 g hydrogen, and 1.251 grams oxygen.

What to find:

The empirical formula for the substance.

Step-by-step solution:

The first step is to convert the number of grams of each element into moles as shown below using the molar masses of H = 1.00784 g/mol and C = 12.011 g/mol and O = 15.999 g/mol

Note: Mole = Mass/Molar mass

Moles C = 3.758g/12.011 g/mol = 0.31 mol

Moles H = 0.316g/1.00784 g/mol = 0.31 mol

Moles O = 1.251g/15.999 g/mol = 0.078 mol

Now, let's divide the number of moles of each element by the smallest number obtained:

C = 0.31/0.078 = 4

H = 0.31/0.078 = 4

O = 0.078/0.078 = 1

The empirical formula for the compound is C₄H₄O₁