To find the final pressure of a gas when it is heated at constant volume, you can use the ideal gas law, which in terms of pressure and temperature can be expressed as:
\[ \frac{P_1}{T_1} = \frac{P_2}{T_2} \]
Where:
- \( P_1 \) is the initial pressure
- \( T_1 \) is the initial temperature
- \( P_2 \) is the final pressure
- \( T_2 \) is the final temperature
In this case, you have:
- \( P_1 = 1 , \text{atm} \)
- \( T_1 = 300 , \text{K} \)
- \( T_2 = 350 , \text{K} \)
Now, rearrange the equation to solve for \( P_2 \):
\[ P_2 = P_1 \times \frac{T_2}{T_1} \]
Substituting the values in:
\[ P_2 = 1 , \text{atm} \times \frac{350 , \text{K}}{300 , \text{K}} = 1 , \text{atm} \times 1.1667 \approx 1.1667 , \text{atm} \]
This is approximately equal to 1.17 atm.
Since this value is closest to option (c) 1.2 atm, the correct answer is:
c. 1.2 atm