How many grams of CO are needed with an excess of Fe2O3 to produce 35.0 g Fe

Question

Solid sodium metal reacts violently with water, producing heat, hydrogen gas, and sodium hydroxide. How many molecules of of hydrogen are formed when 35 g of sodium are added to water?

Answer 1

first, write the balanced reactions, then convert everything from grams to moles, work out the right amount in moles, then convert back to grams or molecules.