Answer:
The temperature of the balloon is approximately 153.4°C.
Step-by-step explanation:
To find the temperature in Celsius of the balloon, we can use the ideal gas law.
Ideal Gas Law

where:
- P is the pressure measured in atmospheres (atm).
- V is the volume measured in liters (L).
- n is the number of moles.
- R is the ideal gas constant (0.08206 L atm mol⁻¹ K⁻¹).
- T is the temperature measured in kelvin (K).
Given values:
- P = 2.5 atm
- V = 35 L
- n = 2.5 mol
- R = 0.08206 L atm mol⁻¹ K⁻¹
Substitute the values into the formula and solve for T:




As the temperature should be in Celsius, we need to convert from kelvin to Celsius by subtracting 273.15:

Therefore, the temperature of the balloon is approximately 153.4°C.