# What are the seven isomers of C4H10O?

Nov 11, 2015

See below.

#### Explanation:

We know from the formula that these isomers contain no rings or double bonds.

The isomers must be alcohols and ethers.

Let's start by drawing the alcohols.

Start with four carbons in a row and put an $\text{OH}$ group in every possible position.

This gives us

1. $\text{CH"_3"CH"_2"CH"_2"CH"_2"OH}$, butan 1-ol

and

2. ${\text{CH"_3"CH"_2"CH(OH)CH}}_{3}$, butan-2-ol

Now use a 3-carbon chain with a ${\text{CH}}_{3}$ on the middle carbon.

This gives

("CH"_3)_2"CHCH"_2"OH", 2-methylpropan-1-ol

and

("CH"_3)_3"COH", 2-methylpropan-2-ol.

Now for the ethers.

This gives

${\text{CH"_3"CH"_2"CH"_2"OCH}}_{3}$, 1-methoxypropane

and

${\text{CH"_3"CH"_2"OCH"_2"CH}}_{3}$, ethoxyethane

Finally, the only choice for a branched-chain ether is

("CH"_3)_2"CHOCH"_3, 2-methoxpropane.

And there are your seven isomers of $\text{C"_4"H"_10"O}$.