I need help with number 5

Find the mass in grams of 1.37x1020 particles of h3po4

According to the vsepr theory what is the shape of a molecule that has a central atom valence three other items with no lone pairs of electrons

Question 5 match each term to its description. match term definition excess reactant a) reactant that can produce a lesser amount of the product limiting reactant b) reactant that can produce more of the product theoretical yield c) amount of product predicted to be produced by the given reactants