Hey anybody free im so bored want to talk

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

How many grams of co(g) are there in 74.5 ml of the gas at 0.933 atm and 30o c?

Sally is making a model of a magnesium atom with an atomic mass number of 24 for her chemistry class. she has foam balls for the protons, neutrons, and electrons. she has added 6 neutrons to her model so far. how many more neutrons does she need to add to complete her neutral atom of magnesium?