Consider three P, Q, R, salts among them P and Q salts have different cations annd also have different coloured polyatomic anion due to charge transfer phenomenon while P and R salts have same cation but have different anions. Salts R decomposes into an acidic gas an a basic gas.
Q. Salt R can not be:

Options

A. `NH_(4)NO_(3)`
B. `(NH_(4))_(2)CO_(3)`
C. `(NH_(4))_(2)S`
D. `NH_(4)Cl`

Explanation

To solve the question regarding salt R, we need to analyze the information provided and the options given. The key points are:

1. Salt R decomposes into an acidic gas and a basic gas.
2. We are given four options to determine which one cannot be salt R.

Let's go through each option step by step:

### Step 1: Analyze the options

**Option 1: NH4NO3 (Ammonium Nitrate)**
- Upon heating, NH4NO3 decomposes to produce nitrous oxide (N2O) and water (H2O).
- Both products (N2O and H2O) are neutral gases, meaning there is no acidic or basic gas produced.
- Therefore, NH4NO3 does not fit the criteria of decomposing into an acidic gas and a basic gas.

**Conclusion for Option 1:** This cannot be salt R.

### Step 2: Check other options

**Option 2: NH4CO3 (Ammonium Carbonate)**
- Upon heating, NH4CO3 decomposes to produce ammonia (NH3) and carbon dioxide (CO2).
- NH3 is a basic gas, while CO2 can react with water to form carbonic acid (H2CO3), which is weakly acidic.
- Therefore, this option fits the criteria of producing an acidic and a basic gas.

**Conclusion for Option 2:** This can be salt R.

**Option 3: NH4S (Ammonium Sulfide)**
- Upon heating, NH4S decomposes to produce ammonia (NH3) and hydrogen sulfide (H2S).
- NH3 is basic and H2S is acidic.
- This option also fits the criteria.

**Conclusion for Option 3:** This can be salt R.

**Option 4: NH4Cl (Ammonium Chloride)**
- Upon heating, NH4Cl decomposes to produce ammonia (NH3) and hydrogen chloride (HCl).
- NH3 is basic and HCl is acidic.
- This option fits the criteria as well.

**Conclusion for Option 4:** This can be salt R.

### Final Conclusion:
Based on the analysis, the only option that does not produce an acidic and a basic gas upon decomposition is **Option 1: NH4NO3 (Ammonium Nitrate)**. Therefore, salt R cannot be NH4NO3.