Limiting Reactants Quiz

In the equation Mg + O2(g) → MgO, how many molecules of Mg on the reactant side do we need to make our equation balance?

• 1

• 2

• 3

• 4

Use the following BALANCED equation: 2C2H6 + 7O2 → 4CO2 + 6H2O. If 15 g of C2H6 react with 45 g of O2, how many grams of water will be produced?

• 22 g H2O

• 23 g H2O

• 27 g H2O

• 28 g H2O

What is the limiting reactant in the equation in item number 2?

• O2

• C2H6

• H2O

• CO2

What is the excess reactant in the equation in item number 2?

• O2

• C2H6

• H2O

• CO2

Consider the following reaction: 2Al + 6HBr →2AlBr3 + 3H2. When 86.9 grams of Al reacts with 401 grams of HBr, how many H2 are formed?

• 5.01 g

• 7.01 g

• 8.01 g

• 10.01 g

What is the limiting reactant in item no. 6?

• Al

• AlBr3

• HBr

• H2

For the excess reactants, how many grams are left over at the end of the reaction?

• 42.3 g

• 44.3 g

• 47.4 g

• 48.4 g

It is reactants that are not used up when the reaction is finished.

• reactants

• limiting reagents

• solute

• excess reagents

It deals with the process that involves rearrangement of the molecular or ionic structure of a substance to form a new substance or product.

• chemical equilibrium

• chemical symbol

• chemical reaction

• stoichiometry

Which of the following is the correct sequence of a chemical equation?

• Reactant → Product

• Reactant +