Compound used in safety matches is :

Options

A. `P_(4)S_(3)`
B. `P_(4)`
C. `P_(2)O_(5)`
D. `PCl_(3)`

Explanation

To determine the compound used in safety matches, we can follow these steps:

### Step 1: Understand the Composition of Safety Matches
Safety matches are designed to ignite safely when struck against a specially prepared surface. The key component that allows this ignition is a chemical compound.

### Step 2: Identify the Chemical Compounds
The video mentions two compounds: P4 (tetraphosphorus) and P4S3 (tetraphosphorus trisulfide).

### Step 3: Reaction of P4S3
The video explains that P4S3 reacts with oxygen (O2) when ignited. The reaction can be represented as follows:

\[ \text{P}_4\text{S}_3 (s) + \text{O}_2 (g) \rightarrow \text{P}_4\text{O}_{10} (s) + \text{SO}_2 (g) \]

- **Reactants**: P4S3 in solid state and O2 in gaseous state.
- **Products**: P4O10 (solid) and SO2 (gaseous).

### Step 4: Conclusion
From the above information, we can conclude that the compound used in safety matches is **P4S3** (tetraphosphorus trisulfide).

### Final Answer
The compound used in safety matches is **P4S3**.

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