Among the following mixiture dipole-dipole as the mojor interaction is present is

Options

A. Benzene and `CCl_4`
B. Benzene and `C_2H_5 OH`
C. `CH_3COCH_3 and CH_3CN`
D. KCL and water

Answer

To determine which mixture has dipole-dipole interactions as the major interaction, we will analyze each option provided.

### Step 1: Analyze Option A (Benzene and CCl4)
- **Structures**: Benzene (C6H6) is a non-polar molecule due to its symmetrical structure. CCl4 (carbon tetrachloride) is also non-polar because of its symmetrical tetrahedral shape.
- **Interactions**: Since both components are non-polar, they do not exhibit dipole-dipole interactions.

**Hint**: Look for the polarity of the molecules in the mixture.

### Step 2: Analyze Option B (Benzene and C2H5OH)
- **Structures**: Benzene is non-polar, while C2H5OH (ethanol) is a polar molecule due to the presence of the hydroxyl (-OH) group.
- **Interactions**: The interaction between a polar and a non-polar molecule is primarily London dispersion forces, not dipole-dipole interactions.

**Hint**: Identify which molecules are polar and which are non-polar.

### Step 3: Analyze Option C (CH3COCH3 and CH3C≡N)
- **Structures**: CH3COCH3 (acetone) is a polar molecule due to the carbonyl (C=O) group. CH3C≡N (acetonitrile) is also polar due to the presence of the nitrile (C≡N) group.
- **Interactions**: Both components are polar, which allows for dipole-dipole interactions to occur.

**Hint**: Check if both molecules in the mixture are polar.

### Step 4: Analyze Option D (KCl and H2O)
- **Structures**: KCl (potassium chloride) is an ionic compound, while H2O (water) is a polar covalent molecule.
- **Interactions**: While KCl can interact with water through ion-dipole interactions, dipole-dipole interactions are not the major type of interaction here.

**Hint**: Consider the nature of the interactions between ionic and polar molecules.

### Conclusion
The mixture that exhibits dipole-dipole interactions as the major interaction is **Option C (CH3COCH3 and CH3C≡N)**, as both components are polar molecules.

**Final Answer**: C (CH3COCH3 and CH3C≡N)