what happens to the mass of gas when the temperature goes up?

Question

what happens to the mass of gas when the temperature goes up

Answer 1

obinna
When the temp. of a gas goes up,it expands thereby increasing its volume and and decreasing its pressure.Mass always remains constant no matter the situation.

Answer 2

PV = nRT; where P is gas pressure, V is contained volume of gas, n is the number of moles of gas in V, R is a fixed number, and T is degrees K

"A mole can also be ... defined as: That quantity of a substance whose mass in grams is the same as its formula weight. For example, iron has an relative atomic mass of 55.845 u, so a mole of iron has a mass of 55.845 grams. "[See source.]

Thus, the number of moles (n) in PV = nRT represents the mass of the gas. Therefore n = PV/RT and as the temperature (T) goes up, the number of moles (mass quantity) must decrease if PV = constant.

PV would be a constant in a confined area (like the cylinder in a car engine) that keeps a constant pressure as the gasoline explodes. And as n decreases with rising T, the exploding gas/air mixture is exhausted. That is, the number of moles and, therefore, mass in the cylinder volume V decreases.

But, if PV <> constant, from PV = nRT, if we hold the mass of the gas fixed (n = constant), as temperature goes up, the volume and/or the pressure of the gas must rise. This would be like the case where a balloon gets hotter. Both the pressure and its volume rise, as seen by the bigger balloon (V) stretched tighter (P). In this case, because the air is trapped inside the balloon, the mass (n moles) remains the same.

Answer 3

The mass always stays the same. The Volume and pressure, however, will increase.

Answer 4

remains the same. the mass is conserved in all physical / chemical processes.