If 15 g of an unknown gas occupies a 2.5-L sealed flask at 5.1 atm at 21.2 C, then calculate the molar mass of this unknown gas.

Which function is performed by earths atmosphere? a. ultraviolet rays are prevented from reaching the ozone layer. b. earths temperature is raised and moderated by trapping in heat c. charged particles from the sun are prevented from reaching earth. d. magnetic charges from space are prevented from reaching earths surface.

What is the volume occupied by 10.0 dm3 of gas at standard pressure after it has been compressedat constant temputure to 500.0 kpa?

What is the number of moles of chemical units represented by 9.03x10^24? and how do i show work? (dumb it down )