From the aqueous solutions of NaCl , HCl(g), `NH_(3),H_(2)O ,CO_(2),MgCl_(2),C_(6)H_(12)O_(6) ` select
The substances containing molecules only .

Explanation

To solve the question of identifying which substances from the given list contain only molecules in their aqueous solutions, we will analyze each substance step by step.

### Step-by-Step Solution:

1. **Identify the substances**: The substances given are NaCl, HCl, NH3, H2O, CO2, MgCl2, and C6H12O6.

2. **Analyze NaCl**:
- NaCl (sodium chloride) is an ionic compound.
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