A quantity of a gas has an absolute pressure of 400 kPa and an absolute temperature of 110 degrees kelvin. When the temperature of the gas is raised to 235 degrees kelvin, what is the new pressure of the gas? (Assume that there's no change in volume.)

a. 3.636 kPa

b. 854.46 kPa

c. 1.702 kPa

d. 510 kPa

You can make sure there's no change in volume by keeping

your gas in a sealed jar with no leaks. Then you can play with

the temperature and the pressure all you want, and you'll know

that the volume is constant.

For 'ideal' gases,

(pressure) times (volume) is proportional to (temperature).

And if volume is constant, then

(pressure) is proportional to (temperature).

So if you increase the temperature from 110K to 235K,

the pressure increases to (235/110) of where it started.

(400 kPa) x (235/110) = 854.55 kPa. (rounded)

Obviously, choice-b is the right one, but

I don't know where the. 46 came from.