In a homologous series, two successive members differ by a .............. group and a molecular mass of ............ amu.

Explanation

To solve the question regarding the differences between successive members of a homologous series, we can break it down into clear steps:

### Step-by-Step Solution:

1. **Understanding Homologous Series**:
- A homologous series is a sequence of organic compounds that have the same functional group and similar chemical properties. Each member of the series differs from the next by a specific unit.

2. **Identifying the Unit of Difference**:
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