Question

A hydrocarbon contain 0.0334 mol of carbon, 0.0668 mol of hydrogen and 0.0167 mol of oxygen. what is the empirical formula of the hydrocarbon.?

Options
a) C3H4O2 b) C4H8O2 c) C2H4O d) CH2O

Answer 1

C

Explanation:

We already know the following:

The molecule contains only `C, H " and " O` atoms.

The number of `C, H," and " O` atoms, in moles.

We can now rewrite the molecular structure of the molecule `CHO` as `C_0.0334H_0.0668O_0.0167` with the given quantities of `C, H, " and " O`.

In order to get these values into their lowest integers, we divide each value by the smallest one, in this case .0167 mol `H`.

`(.0334 " mol " C)/(.0167) = "about 2 moles of C"`
`(.0668 " mol " H)/(.0167) = "about 4 moles of H"`
`(.0167 " mol " O)/(.0167) = "about 1 mole of O"`

Thus the empirical formula will be `C_2H_4O`, which is answer C.