Hg2(NO3)2 + Na2CO3 = NaNO3 + HgCO3 balance this

Plz choose one of the compounds from the table and explain how you know the numbers of atoms in your formula. is it possible for two different compounds to be made from the exact same two elements? why or why not? with a limited number of elements (less than 120 are known), does this mean we also have a small number of compounds or do we have a large number of compounds in this world?

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

Based on its chemical properties, identify the position of each chemical family on the periodic table.