7. A helium balloon has a pressure of 40 psi at 20°C. What will the pressure
be at 40°C? Assume constant volume and mass.
To determine the pressure of a helium balloon at a different temperature, you can use the ideal gas law equation:
P1/T1 = P2/T2
Where:
- P1 is the initial pressure (40 psi)
- T1 is the initial temperature in Kelvin (20°C + 273.15 = 293.15 K)
- P2 is the final pressure (unknown)
- T2 is the final temperature in Kelvin (40°C + 273.15 = 313.15 K)
To find the final pressure, we need to rearrange the equation:
P2 = (P1 × T2) / T1
Now we can plug in the values:
P2 = (40 psi × 313.15 K) / 293.15 K
Calculating this equation will give you the result:
P2 = 42.93 psi
Therefore, the pressure of the helium balloon at 40°C would be approximately 42.93 psi.