Asample of gas is stored in a cylinder. if the temperature is kept constant and the piston moves up to increase the volume what happens to the pressure?

Asyringe contains 56.05 ml of gas at 315.1 k. what volume will that gas occupy if the temperature is increased to 380.5 k? a) 12.41 b) 46.42 c) 67.68 d) 81.74

11. phosphorus-32 is radioactive and has a half life of 14 days. how much of a 124 mg sample of phosphorus-32 is present after 56 days? a) 7.75 mg b) 15.5 mg c) 31.0 mg d) 62.0 mg

How many moles of lead are in 1.50 x 10^12 atoms of lead? could you explain the answer as well and not just give it to me i am refreshing for finals and i need to know how to do it