Chemical Reactions Mock Test

Which law states that mass is not created nor destroyed in an ordinary chemical reaction?

• Law of Definite Composition

• Law of Multiple Proportions

• Law of Mass Conservation

• Law of Action and Reaction

A substance which slows down the rate of reaction but remains chemically unchanged is called

• reactant

• inhibitor

• product

• catalyst

 Which of the following does NOT affect the rate of reaction of solids and liquids?

•  temperature

• concentration

• pressure

• surface area

What is the type of reaction when sodium nitrate, AgNO₃ reacts with potassium chloride, KCl?

• Single displacement reaction

• Combustion reaction

• Double displacement reaction

• Decomposition reaction

What do you call the “energy barrier” referred to in a chemical reaction?

•   potential energy

• internal energy

• kinetic energy

• activation energy

What is the balanced chemical equation for the reaction between magnesium, Mg, and oxygen, O₂, forming magnesium oxide, MgO?

• 2Mg + O₂ -> 2MgO

• MgO + O₂ -> Mg₂O₂

• 2Mg + O -> Mg₂O

• Mg + O -> MgO₂

Which of the following is not a necessary condition for a chemical reaction to proceed?

•       Heat must be applied.

• The reactant particles must collide with each other.

• The collisions must have enough energy to overcome the activation energy.

• The reactants must form new bonds to produce products.

 

In a balanced equation for the hypothetical reaction, C₂D  +  O₂  =   C₂O_{2,  +}  D₂, C₂D must have a coefficient of 

• 1

• 2

• 3

• 4

Magnesium fluoride reacts with potassium  sulfate and forms magnesium sulfate and potassium fluoride. Which of the following statements is correct according to the law of conservation of mass?

• The total mass of reactants taken is greater than the total mass of the products.

• The total mass of reactants taken is less than the total mass of the products.

• The total mass of reactants taken is equal to the total mass of the products.

• The total amount of product is totally independent of the total amount of the reactant.

 If the law of conservation of mass holds true, how much lithium fluoride will react with 50.0 g of potassium nitrate to produce 32 g of lithium nitrate and 45.27 g of potassium fluoride?

• 27.27

• 77.27

• 32

• 45.27