# Question #a7e06

Jul 3, 2015

The compound's empirical formula is ${C}_{7} {H}_{16}$.

#### Explanation:

Here's how you can determine your compound's empirical formula.

You know that its percent composition is 84% carbon and 16% hydrogen. This means that a 100-g sample of your compound will contain 84 g of carbon and 16 g of hydrogen.

Use carbon and hydrogen's molar masses to determine how many moles of each you'd get in a 100-g sample.

$\text{For C": (84cancel("g"))/(12.0cancel("g")/"mol") = "7 moles}$

$\text{For H": (16cancel("g"))/(1.008cancel("g")/"mol") = 15.87 ~= "16 moles}$

The simplest ratio between 7 and 16 is actually $7 : 16$, which means that the empirical formula looks like this

${C}_{7} {H}_{16}$

You get 7 moles of carbon and 16 moles of hydrogen for every 100-g of your compound.