which of the following are used for making the explosive of crackers is

Options

A. sodium chloride
B. salt petre
C. soda
D. blue vitriol

Explanation

To determine which of the given compounds are used for making the explosive of crackers, let's analyze each option step by step.

### Step 1: Identify the Compounds
The compounds mentioned are:
1. Sodium Chloride (NaCl)
2. Salt Peter (KNO3)
3. Soda (Sodium Carbonate, Na2CO3)
4. Blue Vitriol (Copper(II) Sulfate, CuSO4)

### Step 2: Analyze Sodium Chloride (NaCl)
- **Description**: Sodium chloride is commonly known as table salt.
- **Usage**: It is primarily used in food and as an anti-freezing agent.
- **Conclusion**: Sodium chloride does not have explosive properties and is not used in making explosives.

### Step 3: Analyze Salt Peter (KNO3)
- **Description**: Salt Peter, also known as potassium nitrate, is a chemical compound.
- **Usage**: It is known for its role in explosives. It acts as an oxidizing agent and can react with reducing agents to produce explosive reactions.
- **Conclusion**: Salt Peter is indeed used in making explosives, including those in crackers.

### Step 4: Analyze Soda (Sodium Carbonate, Na2CO3)
- **Description**: Soda, or washing soda, is a sodium salt of carbonic acid.
- **Usage**: It is mainly used in cleaning agents and does not have explosive properties.
- **Conclusion**: Soda is not used in making explosives.

### Step 5: Analyze Blue Vitriol (CuSO4)
- **Description**: Blue vitriol is crystalline copper sulfate.
- **Usage**: It is primarily used as a fungicide and herbicide and can be toxic.
- **Conclusion**: Blue vitriol does not have explosive properties and is not used in making explosives.

### Final Conclusion
From the analysis, the only compound that is used for making the explosive of crackers is **Salt Peter (KNO3)**.

### Summary of Findings
- Sodium Chloride (NaCl): Not used in explosives.
- Salt Peter (KNO3): Used in explosives.
- Soda (Na2CO3): Not used in explosives.
- Blue Vitriol (CuSO4): Not used in explosives.

### Answer
**Salt Peter (KNO3)** is used for making the explosive of crackers.

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