Limiting Reagents and Molarity Quiz

Which of the following is the limiting reagent in the reaction: 2H₂ + O₂ → 2H₂O when 4 moles of H₂ and 1 mole of O₂ are mixed?

• H₂

• O₂

• H₂O

• Both are limiting

What does the limiting reagent determine in a chemical reaction?

• Rate of reaction

• Maximum amount of product formed

• Volume of reactants

• Color of the product

The substance remaining after the limiting reagent is consumed is called:

• Major product

• Excess reagent

• Catalyst

• Byproduct

Which is NOT a factor considered in identifying the limiting reagent?

• Number of moles

• Stoichiometric ratio

• Volume or mass of reactant

• Color change in reaction

In the formation of water, if 2 moles of H₂ react with 3 moles of O₂, which is the excess reagent?

• H₂

• O₂

• H₂O

• Both are excess

What is the unit of molarity?

• Moles per kilogram

• Moles per meter

• Moles per liter

• Grams per liter

If 1 mole of NaCl is dissolved to make 2 liters of solution, the molarity of the solution is:

• 1 M

• 2 M

• 0.5 M

• 0.25 M

Molarity is defined as the number of moles of solute per:

• Milliliter of solvent

• Liter of solution

• Gram of solution

• Liter of solvent

Which reactant is limiting in the reaction 2A + 4B → 3C + 4D if 5 moles of A react with 6 moles of B?

• A

• B

• C

• D

To calculate the number of moles of solute in 500 mL of a 2 M solution, the correct calculation would be:

• 2 × 0.5 = 1 mole

• 2 × 2 = 4 moles

• 0.5 ÷ 2 = 0.25 mole

• 2 ÷ 0.5 = 4 moles