2.00 L of a gas at 20°C and 0.8 atm is brought to standard temperature and pressure what will be the new gas volume?
hint: us the combined gas law. the volume at STP is 273 K and pressure is 1 atm.

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?