A pure NaCl solution with concentration more than 0.91% is called hypertonic/hypotonic.

Explanation

To determine whether a pure NaCl solution with a concentration greater than 0.91% is hypertonic or hypotonic, we can follow these steps:

### Step 1: Understand the Definitions
- **Hypertonic Solution**: A solution that has a higher concentration of solutes compared to another solution.
- **Hypotonic Solution**: A solution that has a lower concentration of solutes compared to another solution.
- **Isotonic Solution**: A solution that has the same concentration of solutes as another solution.

### Step 2: Identify the Reference Concentration
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