Dalton's law of partial pressures is not applicable to

Options

A. `H_(2)` and `N_(2)` mixture
B. `H_(2)` and `Cl_(2)` mixture
C. `H_(2)` and `CO_(2)` mixture
D. none of these

Explanation

To determine when Dalton's law of partial pressures is not applicable, we need to understand the conditions under which this law holds true. Here’s a step-by-step solution:

### Step 1: Understand Dalton's Law of Partial Pressures
Dalton's Law states that in a mixture of non-reacting gases, the total pressure exerted is equal to the sum of the partial pressures of each individual gas. Mathematically, it can be expressed as:
\[ P_{total} = P_1 + P_2 + P_3 + ... + P_n \]
where \( P_1, P_2, \) etc. are the partial pressures of the individual gases.

### Step 2: Identify the Conditions for Applicability
Dalton's Law is applicable only to non-reactive gases. This means that the gases in the mixture must not undergo any chemical reactions with each other. If the gases react, they will change the number of moles of the gases present, which affects the total pressure and the partial pressures.

### Step 3: Analyze the Given Gases
In the question, we are given pairs of gases:
1. H2 and N2
2. H2 and Cl2
3. H2 and CO2

- **H2 and N2**: These gases are non-reactive under normal conditions, so Dalton's law is applicable.
- **H2 and Cl2**: These gases are reactive. They can react to form HCl gas. Therefore, Dalton's law is not applicable here.
- **H2 and CO2**: These gases are also generally considered non-reactive under standard conditions, so Dalton's law is applicable.

### Step 4: Conclusion
Dalton's law of partial pressures is not applicable to the pair of gases **H2 and Cl2** because they can react with each other to form HCl.

### Final Answer
Dalton's law of partial pressures is not applicable to **H2 and Cl2**.

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