Calculate the normality of `NaOH` when `2 g` is present in `800 mL` solution.

Answer

To calculate the normality of NaOH when 2 g is present in 800 mL of solution, we will follow these steps:

### Step 1: Determine the molar mass of NaOH
The molar mass of NaOH can be calculated as follows:
- Sodium (Na) = 23 g/mol
- Oxygen (O) = 16 g/mol
- Hydrogen (H) = 1 g/mol

So, the molar mass of NaOH = 23 + 16 + 1 = 40 g/mol.

### Step 2: Calculate the number of moles of NaOH
To find the number of moles of NaOH, we use the formula:
\[ \text{Number of moles} = \frac{\text{mass (g)}}{\text{molar mass (g/mol)}} \]
Substituting the values:
\[ \text{Number of moles} = \frac{2 \text{ g}}{40 \text{ g/mol}} = 0.05 \text{ moles} \]

### Step 3: Convert the volume of the solution from mL to L
The volume of the solution is given as 800 mL. To convert this to liters:
\[ \text{Volume (L)} = \frac{800 \text{ mL}}{1000} = 0.8 \text{ L} \]

### Step 4: Calculate the molarity of the solution
Molarity (M) is defined as the number of moles of solute per liter of solution:
\[ \text{Molarity} = \frac{\text{Number of moles}}{\text{Volume (L)}} \]
Substituting the values:
\[ \text{Molarity} = \frac{0.05 \text{ moles}}{0.8 \text{ L}} = 0.0625 \text{ M} \]

### Step 5: Calculate the normality of the solution
For NaOH, the n-factor is 1 because it can donate one hydroxide ion (OH⁻) per molecule. Therefore, normality (N) is equal to molarity (M):
\[ \text{Normality} = \text{Molarity} \times \text{n-factor} = 0.0625 \text{ M} \times 1 = 0.0625 \text{ N} \]

### Final Answer
The normality of the NaOH solution is **0.0625 N**.

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