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Agas mixture with a total pressure of 745 mmhg contains each of the following gases at the indicated partial pressures: co2, 245 mmhg ; ar, 119 mmhg ; and o2, 163 mmhg . the mixture also contains helium gas. part a what is the partial pressure of the helium gas? phe p h e = nothing mmhg request answer part b what mass of helium gas is present in a 10.2-l sample of this mixture at 283 k ? m m = nothing g request answer

What happens to the average kinetic energy of a gas when the particles of the gas collide against each other at a constant temperature and volume? explain your answer.

How much energy is required to vaporize 2 kg of copper? a 4730 kj b 207kj c 9460 kj d 414kj