Which of the following statements are usually correct for carbon compounds ? These
are good conductors of electricity.
are poor conductors of electricity.
have strong forces of attraction between their molecules.
do not have strong forces of attraction between their molecules.

Options

A. (i) and (iii)
B. (ii) and (iii)
C. (i) and (iv)
D. (ii) and (iv)

Explanation

To determine which statements about carbon compounds are usually correct, let's analyze each statement step by step.

### Step 1: Analyze the first statement
**Statement:** Carbon compounds are good conductors of electricity.

**Explanation:** Carbon compounds, especially those that are covalent in nature, do not have free electrons available for conduction. Since electrical conductivity requires free-moving charged particles (like electrons), carbon compounds are generally not good conductors of electricity.

**Conclusion:** This statement is **incorrect**.

### Step 2: Analyze the second statement
**Statement:** Carbon compounds are poor conductors of electricity.

**Explanation:** As mentioned earlier, carbon compounds lack free electrons because all the valence electrons of carbon are involved in covalent bonding. This results in a lack of free-moving charged particles, making them poor conductors of electricity.

**Conclusion:** This statement is **correct**.

### Step 3: Analyze the third statement
**Statement:** Carbon compounds have strong forces of attraction between their molecules.

**Explanation:** The forces of attraction between molecules in carbon compounds (which are typically covalent) are generally weaker than those in ionic compounds. Covalent bonds involve shared electrons, and while they are strong bonds between atoms, the intermolecular forces (forces between the molecules) are relatively weak.

**Conclusion:** This statement is **incorrect**.

### Step 4: Analyze the fourth statement
**Statement:** Carbon compounds do not have strong forces of attraction between their molecules.

**Explanation:** As discussed, the intermolecular forces in carbon compounds are weak due to the nature of covalent bonding. This means that the forces of attraction between the molecules are indeed not strong.

**Conclusion:** This statement is **correct**.

### Final Answer
Based on the analysis:
- The correct statements are:
- Carbon compounds are poor conductors of electricity.
- Carbon compounds do not have strong forces of attraction between their molecules.

Thus, the correct options are the second and fourth statements.

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