The compounds `CH_(3)CH = CHCH_(3)` and `CH_(3)CH_(2)CH = CH_(2)`

Options

A. Are tautomers
B. Are position isomers
C. Contain same number of `sp^(3) - sp^(3), sp^(3) - sp^(2)` and `sp^(2) - sp^(2)` carbon-carbon bonds
D. Exist together in dynamic equilibrium

Explanation

To analyze the compounds \( CH_3CH=CHCH_3 \) and \( CH_3CH_2CH=CH_2 \), we will first identify their structures and then determine their relationship.

### Step 1: Identify the Compounds
1. The first compound \( CH_3CH=CHCH_3 \) can be represented as:
- The carbon skeleton: \( C_4H_8 \) (butene).
- The double bond is located between the second and third carbon atoms.
- This compound is named **But-2-ene**.

2. The second compound \( CH_3CH_2CH=CH_2 \) can be represented as:
- The carbon skeleton: \( C_4H_8 \) (butene).
- The double bond is located between the first and second carbon atoms.
- This compound is named **But-1-ene**.

### Step 2: Determine the Relationship
- Both compounds have the same molecular formula \( C_4H_8 \), indicating they are isomers.
- They differ in the position of the double bond, which makes them **positional isomers**.

### Conclusion
The relationship between the two compounds \( CH_3CH=CHCH_3 \) (But-2-ene) and \( CH_3CH_2CH=CH_2 \) (But-1-ene) is that they are **positional isomers**.