Hows does one determine a molecular formula from the emprical formula?

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?

What will most likely happen when two bromine atoms bond together?

If two objects at different te,peraure are in contact with each other what happens to their temperature