Baking powder contains sodium hydrogen carbonate and

Options

A. tartaric acid
B. washing soda
C. calcium chloride
D. acetic acid .

Explanation

To answer the question about what baking powder contains, we can break it down into a step-by-step solution.

### Step-by-Step Solution:

1. **Identify the Components of Baking Powder:**
Baking powder is a leavening agent commonly used in baking. It typically contains sodium hydrogen carbonate (also known as baking soda) and an acid.

2. **Recognize the Acid Used:**
The acid that is commonly found in baking powder is tartaric acid. The chemical formula for tartaric acid is C4H6O6.

3. **Understand the Reaction:**
When sodium hydrogen carbonate (NaHCO3) reacts with tartaric acid (C4H6O6), a chemical reaction occurs. This reaction produces sodium hydroxide (NaOH) and releases carbon dioxide (CO2) and water (H2O), which helps in the leavening process.

4. **Write the Reaction:**
The reaction can be summarized as follows:
\[ \text{NaHCO}_3 + \text{C}_4\text{H}_6\text{O}_6 \rightarrow \text{NaOH} + \text{CO}_2 + \text{H}_2\text{O} \]

5. **Conclusion:**
Therefore, baking powder contains sodium hydrogen carbonate and tartaric acid.

### Final Answer:
Baking powder contains sodium hydrogen carbonate and tartaric acid.

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