RCI is treated with Li in ether solution to form R-Li. R-Li reacts with `H_2O` to form isopentane. RCI also reacts with Na to form 2,7-dimethyloctane. What is the structure of RCI?

Explanation

To solve the problem, we need to determine the structure of RCl based on the reactions described. Let's break it down step by step.

### Step 1: Understanding the Reactions
1. **RCl + Li → RLi**: This reaction indicates that RCl is being converted to an organolithium compound (RLi) using lithium in an ether solution.
2. **RLi + H2O → Isopentane**: The organolithium compound (RLi) reacts with water to form isopentane. Isopentane has the structure:
\[ \text{CH}_3 - \text{CH} - \text{CH}_2 - \text{CH}_3 \]
...