Which is more reactive, `C_(6)H_(6) or C_(6)D_(6)` towards electrophilic substitution?

Explanation

To determine which compound, \( C_6H_6 \) (benzene) or \( C_6D_6 \) (deuterated benzene), is more reactive towards electrophilic substitution, we can analyze the bond characteristics and the reaction mechanism involved.

### Step-by-Step Solution:

1. **Understanding the Compounds**:
- \( C_6H_6 \) is benzene, which has six hydrogen atoms attached to a carbon ring.
- \( C_6D_6 \) is deuterated benzene, where each hydrogen atom is replaced by deuterium (a heavier isotope of hydrogen).

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