An effusion container is filled with 2 l of an unknown gas. it takes 350 s for the gas to effuse into a vacuum. from the same container under the same conditions--same temperature and initial pressure, it takes 229 s for 2.00 l of o2 gas to effuse. calculate the molar mass (in grams/mol) of the unknown gas.

Kc = 0.040 for the system below at 450oc. if a reaction is initiated with 0.40 mole of cl2 and 0.40 mole of pcl3 in a 2.0 liter container, what is the equilibrium concentration of cl2 in the same system? pcl5(g) ⇄ pcl3(g) + cl2(g)

How many atoms are there in 5.70 mol of mg

Consider hydrogen in an excited state n = 5n=5 that emits photons to reach the ground state. there are various possible transitions other than straight to the ground state that can occur; for example, it can drop to the n = 3n=3 state followed by the n = 3n=3 to the ground state transition. which of the possible transitions will result in the emission of a photon in the visible region?