Please help with these two questions! I need it to be step by step because I don’t understand it at all.

If the atomic mass of an atom is 34 and the atom contains 13 protons, how many neutrons does the atom contain?

How many moles of carbon dioxide will form if 2.5 moles of c3h8 is burned

Americium-241 undergoes fission to produce three neutrons per fission event. if a neutron-absorbing material is mixed in with this sample so that the rate of neutron production drops down to 1.8 neutrons per fission event, which will be effective at achieving a critical mass? check all that apply. remove a deflective shield surrounding the sample. remove absorbent material mixed in with the sample. compress the sample of americium-241.