The percentage of oxygen in NaOH is

Options

A. (a)`40`
B. (b)`60`
C. (c)`8`
D. (d)`10`

Explanation

To calculate the percentage of oxygen in sodium hydroxide (NaOH), we can follow these steps:

### Step 1: Determine the molecular mass of NaOH
- Sodium (Na) has an atomic mass of 23 g/mol.
- Oxygen (O) has an atomic mass of 16 g/mol.
- Hydrogen (H) has an atomic mass of 1 g/mol.

The molecular mass of NaOH can be calculated as follows:
\[ \text{Molecular mass of NaOH} = \text{Atomic mass of Na} + \text{Atomic mass of O} + \text{Atomic mass of H} \]
\[ = 23 + 16 + 1 = 40 \text{ g/mol} \]

### Step 2: Determine the mass of oxygen in NaOH
In NaOH, there is one oxygen atom. Therefore, the mass of oxygen in NaOH is:
\[ \text{Mass of oxygen} = 16 \text{ g/mol} \]

### Step 3: Calculate the percentage of oxygen in NaOH
The percentage of oxygen can be calculated using the formula:
\[ \text{Percentage of oxygen} = \left( \frac{\text{Mass of oxygen}}{\text{Molecular mass of NaOH}} \right) \times 100 \]
Substituting the values we have:
\[ \text{Percentage of oxygen} = \left( \frac{16}{40} \right) \times 100 \]
\[ = 0.4 \times 100 = 40\% \]

### Final Answer
The percentage of oxygen in NaOH is **40%**.

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