Products and reactants are substances. The first one (the products) are obtained when the reactants are changed. The process of change of one element into another is called chemical reaction. The reactants are transformed during the chemical reaction into products. Limiting reactant is the reactant which defines the amount of product as a a result of the reaction. This reactant is also called limiting reagent.
Because they both have the same push of gravity. Gravity affects all objects equally. If you drop an egg and a watermelon at the same time they would both collide with the floor at the same time.
