The gas pressure in an aerosol can is 1.8 atm at 25°c. if the gas is an ideal gas, what pressure would develop in the can if it were heated to 475°c

For ideal gases at constant volume, you can use the law of Gay - Lussac:

P / T = constant = > P1 / T1 = P2 / T2

=> P2 = T2 * P1 / T1

And remember you have to use absolute scale of temperature.

T1 = 25 + 273.15 = 298.15 K

T2 = 475 + 273.15 = 748.15 K

=> P2 = 748.15 K * 1.8 atm / 298.15 K = 4.5 atm

Answer: 4.5 atm