When an ant stings a person, the solution of substance A is rubbed on the stung area of the skin to get relief from pain. The substance A is also used in kitchen for cooking purposes. Another susbtance B is sour in taste and contains an organic acid C. It is used in making pickles. When a solution of A is mixed with B, then a change D takes place to produce bubbles of gas E.
Name the acid C.

Answer

To solve the question step by step, let's break down the information provided and analyze it:

### Step 1: Identify Substance A
The question states that substance A is used to relieve pain from an ant sting and is also used in cooking. Ant stings are acidic in nature, and to neutralize this acidity, a base is needed. A common base used in cooking is baking soda.

**Substance A = Baking Soda (NaHCO₃)**

### Step 2: Identify Substance B
Substance B is described as sour in taste, contains an organic acid, and is used in making pickles. The most common substance that fits this description is vinegar, which is known for its sour taste and is used in pickling.

**Substance B = Vinegar**

### Step 3: Identify Acid C
Vinegar contains acetic acid, which is the organic acid referred to in the question.

**Acid C = Acetic Acid (CH₃COOH)**

### Step 4: Understand the Reaction
When baking soda (substance A) is mixed with vinegar (substance B), a chemical reaction occurs. This reaction produces sodium acetate, water, and carbon dioxide gas. The formation of bubbles indicates the release of carbon dioxide.

**Change D = Chemical Change**
**Gas E = Carbon Dioxide (CO₂)**

### Conclusion
The acid C mentioned in the question is acetic acid.

**Final Answer: Acid C = Acetic Acid (CH₃COOH)**

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