Calculate the pH of the following solutions :
0.3 g of NaOH dissolve in water to give 200 mL of solutions.

Explanation

To calculate the pH of a solution made by dissolving 0.3 g of NaOH in 200 mL of water, follow these steps:

### Step 1: Calculate the molarity of the NaOH solution.
1. **Find the molar mass of NaOH**:
- Sodium (Na) = 23 g/mol
- Oxygen (O) = 16 g/mol
- Hydrogen (H) = 1 g/mol
- Molar mass of NaOH = 23 + 16 + 1 = 40 g/mol
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