If three unreactive gases having partial pressures , `P_(A) , P_(B)` and `P_(C)` and their moles are 1 , 2 and 3 respectively then their total pressure will be

Options

A. `P = P_(A) + P_(B) + P_(C)`
B. `P = (P_(A) + P_(B) + P_(C))/(6)`
C. `P = (P_(A) + P_(B) + P_(C))/(3)`
D. None

Answer

To solve the problem of finding the total pressure of a mixture of three unreactive gases with given partial pressures, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Dalton's Law of Partial Pressures**:
Dalton's Law states that the total pressure of a mixture of non-reacting gases is equal to the sum of the partial pressures of each individual gas in the mixture.

2. **Identifying the Given Information**:
- We have three gases:
- Gas A with partial pressure \( P_A \) and 1 mole
- Gas B with partial pressure \( P_B \) and 2 moles
- Gas C with partial pressure \( P_C \) and 3 moles

3. **Applying Dalton's Law**:
According to Dalton's Law, the total pressure \( P \) can be expressed as:
\[ P = P_A + P_B + P_C \]
Here, \( P_A \), \( P_B \), and \( P_C \) are the partial pressures of gases A, B, and C respectively.

4. **Conclusion**:
Since the moles of the gases do not affect the total pressure in this case (as they are unreactive), we can directly sum the partial pressures to find the total pressure of the mixture.

### Final Answer:
Thus, the total pressure \( P \) of the mixture of the three unreactive gases is:
\[ P = P_A + P_B + P_C \]