What is cyclopentane with a butane called?

Depending upon which carbon the cyclopentane is attached it is butyl cyclopentane. It might be sec butyl or tert butyl cyclopentane.

Cyclopentane with a butane is called a cyclopentylbutane.

To determine the name, you can follow these steps:

1. Identify the number of carbon atoms in each chain.
- Cyclopentane has 5 carbon atoms in a ring structure.
- Butane has 4 carbon atoms in a straight chain.

2. Determine the prefix for each carbon chain.
- Cyclopentane is a cyclic compound, so it is named as a cyclo-.
- Butane is an open-chain alkane, so it is named as but-.

3. Combine the prefixes and add the appropriate ending.
- The prefix for cyclopentane (cyclo-) is placed in front of butane (but-) to give cyclopentylbutane.

Therefore, the name for the compound consisting of a cyclopentane ring connected to a butane chain is cyclopentylbutane.