Write the structural formula of isobutyronitrile.

Explanation

To write the structural formula of isobutyronitrile, we can follow these steps:

### Step 1: Understand the Name
The name "isobutyronitrile" indicates that we are dealing with a nitrile compound derived from isobutyric acid. The prefix "iso" indicates that there is a branched structure.

### Step 2: Determine the Carbon Backbone
The root "but" in isobutyronitrile indicates that there are four carbon atoms in the main chain. In isobutyronitrile, one of these carbons will be part of the nitrile functional group (-C≡N).

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