Question

draw ch₃ch(ch₃)ch₂cho

Explanation:

The compound is 3-methylbutanal. First, identify the parent chain: the aldehyde group (-CHO) gives the suffix -al, so the parent chain is 4 carbons long (butanal). A methyl substituent is on the 3rd carbon. The structure has an aldehyde terminal group, with the 3rd carbon bonded to a methyl instead of two hydrogens.

Answer:

The structural formula (condensed line-angle structure description and full Lewis structure breakdown):

1. Line-angle structure: A 4-carbon chain, where the first carbon is the aldehyde group (double-bonded to O and single-bonded to H), and the 3rd carbon has a methyl branch attached.

Full condensed structure: $\text{CH}_3\text{CH}(\text{CH}_3)\text{CH}_2\text{CHO}$ expanded to:

$$\begin{align*} &\quad\quad\text{H}\\ &\quad\quad|\\ \text{H}_3\text{C}-\text{CH}-\text{CH}_2-\text{C}=\text{O}\\ &\quad\quad|\\ &\quad\quad\text{CH}_3 \end{align*}$$