A 2.007 g sample of a hydrocarbon is combusted to give 1.389 g of H 2O and 6.785 g of CO 2. What is the empirical formula of the compound? a. CH2 b. C2Hw c. C3H4 d. CH e. C5H12

The empirical formula for the given compound is CH

Explanation:

The chemical equation for the combustion of hydrocarbon follows:

where, 'x', and 'y' are the subscripts of Carbon and hydrogen respectively.

We are given:

Mass of

Mass of

We know that:

Molar mass of carbon dioxide = 44 g/mol

Molar mass of water = 18 g/mol

For calculating the mass of carbon:

In 44 g of carbon dioxide, 12 g of carbon is contained.

So, in 21.33 g of carbon dioxide, of carbon will be contained.

For calculating the mass of hydrogen:

In 18 g of water, 2 g of hydrogen is contained.

So, in 4.366 g of water, of hydrogen will be contained.

To formulate the empirical formula, we need to follow some steps:

Moles of Carbon =

Moles of Hydrogen =

For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is 0.154 moles.

For Carbon =

For Hydrogen =

The ratio of C : H = 1 : 1

Hence, the empirical formula for the given compound is CH

the only liquid elements at standard temperature and pressure are bromine (br) and mercury (hg). although, elements caesium (cs), rubidium (rb), francium (fr) and gallium (ga) become liquid at or just above room temperature.

explanation: