Given the balanced equation, calculate the mass of product that can be prepared from 2.70 g of zinc metal.
2zn(s)+o2(g)→2zno(s)

The mass of zinc is equal to 65.38 g/mol. Since there are 2 mols of zinc in the reactant, the total amount is 130.76 g. For ZnO, the molar mass is 81.38. Multiplying this by 2, the answer is 162.76 g.
By ratio and proportion,
                                    130.76 g/ 162.76 g = 2.70 g/ x
The value of x from the equation is 3.36 g. Therefore, 3.36 grams of ZnO will be prepared. 

The reaction will shift to the right