Anyone wanna talk im having a really hard time rn and i just cant rn

How will the emission of an alpha particle affect the atomic number of an atom

Used the balanced equation 2h2+ o2 - -> 2h2o. if you have 7.2 grams of o2 , how many grams of h2o can you produce ?

Calculate the energy required to ionize a hydrogen atom to an excited state where the electron is initially in the n = 5 energy level. report your answer in kilojoules