Answer:
![\large \boxed{\text{12.0 atm}}](https://img.qammunity.org/2021/formulas/chemistry/college/u1reni3y0tancn3koics0rk5ntes3r0phr.png)
Step-by-step explanation:
The volume and amount of gas are constant, so we can use Gay-Lussac’s Law:
At constant volume, the pressure exerted by a gas is directly proportional to its temperature.
\dfrac{p_{1}}{T_{1}} = \dfrac{p_{2}}{T_{2}}
Data:
p₁ = 9.00 atm; T₁ = 28.0 °C
p₂ = ?; T₂ = 129.0 °C
Calculations:
1. Convert the temperatures to kelvins
T₁ = (28.0 + 273.15) K = 301.15
T₂ = (129.0 + 273.15) K = 402.15
2. Calculate the new pressure
![\begin{array}{rcl}(9.00)/(301.15) & = & (p_(2))/(402.15)\\\\0.02989 & = & (p_(2))/(402.15)\\\\0.02989 * 402.15 &=&p_(2)\\p_(2) & = & \textbf{12.0 atm}\end{array}\\\text{The new pressure is $\large \boxed{\textbf{12.0 atm}}$}](https://img.qammunity.org/2021/formulas/chemistry/college/iu5d8qwiy0ihn2qrsbsvdxm9lw45pssl2r.png)