Out of the following substances, the example of alkali is

Options

A. `HNO_3`
B. NaOH
C. `AlCl_3`
D. `NaHCO_3`

Answer

To determine which of the given substances is an example of an alkali, we need to follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of Alkali**:
Alkalis are defined as strong bases that dissolve in water. They are typically the hydroxides of alkali metals.

2. **Identify Common Alkalis**:
Common examples of alkalis include sodium hydroxide (NaOH), potassium hydroxide (KOH), and lithium hydroxide (LiOH). These are the hydroxides of alkali metals.

3. **Analyze the Options Provided**:
We need to evaluate each option to see if it fits the definition of an alkali:
- **Option 1: HNO3** - This is nitric acid, which is not an alkali.
- **Option 2: NaOH** - This is sodium hydroxide, which is a strong base and fits the definition of an alkali.
- **Option 3: AlCl3** - This is aluminum chloride, which is not an alkali.
- **Option 4: NaHCO3** - This is sodium bicarbonate (baking soda), which is not classified as a strong alkali.

4. **Select the Correct Answer**:
Based on the analysis, the only substance that qualifies as an alkali is **NaOH** (sodium hydroxide).

### Conclusion:
The correct answer is **Option 2: NaOH**.

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