Chemical Reactions: Master the Basics with Interactive Quizzes

Question 1

Which type of chemical reaction involves the formation of a solid precipitate?

Accepted Answer

Double displacement reaction

Answer

Acid-base reaction

Answer

Redox reaction

Answer

Combination reaction

Question 2

What is the conjugate acid of the base NH₃?

Accepted Answer

NH₄⁺

Answer

NH₂⁻

Answer

H₂N⁺

Answer

N³⁻

Question 3

Which of the following species acts as a Lewis base?

Accepted Answer

Hydroxide ion (OH⁻)

Answer

Hydrogen ion (H⁺)

Answer

Aluminum chloride (AlCl₃)

Answer

Sulfate ion (SO₄²⁻)

Question 4

Which of the following is NOT a fundamental type of chemical reaction?

Accepted Answer

Fermentation

Answer

Neutralization

Answer

Oxidation-reduction

Answer

Decomposition

Question 5

In a stoichiometric reaction, which of the following is true?

Accepted Answer

Reactants and products are present in equivalent amounts

Answer

Reactants and products are present in non-equivalent amounts

Answer

The equilibrium constant is less than 1

Answer

The reaction rate is fast

Question 6

What is the activation energy of a reaction?

Accepted Answer

The minimum amount of energy required for a reaction to occur

Answer

The maximum amount of energy released in a reaction

Answer

The difference in energy between reactants and products

Answer

The rate at which a reaction occurs

Question 7

Which of the following is a catalyst?

Accepted Answer

Platinum

Answer

Sodium chloride

Answer

Iron oxide

Answer

Hydrochloric acid

Question 8

What is the role of a catalyst in a chemical reaction?

Accepted Answer

Provides an alternative reaction pathway with a lower activation energy

Answer

Increases the activation energy

Answer

Decreases the rate of reaction

Answer

Changes the products of the reaction

Question 9

Which of the following is NOT a type of chemical reaction?

Accepted Answer

Chemical change

Answer

Combination

Answer

Decomposition

Answer

Single displacement

Question 10

What is the mole ratio of magnesium to oxygen in magnesium oxide (MgO)?

Accepted Answer

1:1

Answer

1:2

Answer

2:1

Answer

Cannot be determined from the information given

Question 11

Which of the following is a redox reaction?

Accepted Answer

2Na + Cl₂ → 2NaCl

Answer

NaOH + HCl → NaCl + H₂O

Answer

MgO + H₂O → Mg(OH)₂

Answer

C₂H₅OH → C₂H₄ + H₂O

Question 12

What is the oxidation number of sulfur in sulfuric acid (H₂SO₄)?

Accepted Answer

+6

Answer

-2

Answer

+2

Answer

+4

Question 13

What is the equilibrium constant expression for the following reaction: N₂(g) + 3H₂(g) ⇌ 2NH₃(g)?

Accepted Answer

K = [N₂][H₂]³/[NH₃]²

Answer

K = [NH₃]²/[N₂][H₂]³

Answer

K = [NH₃]/[N₂][H₂]³

Answer

K = [N₂][H₂]³/[NH₃]

Question 14

Which of the following is a catalyst?

Accepted Answer

Platinum

Answer

Sodium chloride

Answer

Water

Answer

Sodium hydroxide

Question 15

Balance the following chemical equation: C₂H₅OH + O₂ → CO₂ + H₂O.

Accepted Answer

2 C₂H₅OH + 5 O₂ → 4 CO₂ + 6 H₂O

Answer

C₂H₅OH + 3 O₂ → 2 CO₂ + 3 H₂O

Answer

C₂H₅OH + 2 O₂ → 2 CO₂ + 3 H₂O

Answer

C₂H₅OH + O₂ → CO₂ + 2 H₂O

Question 16

Which of the following reactions is exothermic (releases heat)?

Accepted Answer

Combustion of methane

Answer

Dissolution of sodium hydroxide in water

Answer

Neutralization of hydrochloric acid with sodium hydroxide

Answer

Melting of ice

Question 17

Which of the following reactions involves a transfer of electrons?

Accepted Answer

2Na + 2H₂O → 2NaOH + H₂

Answer

CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂

Answer

2NH₃ + H₂SO₄ → (NH₄)₂SO₄

Answer

CH₄ + 2O₂ → CO₂ + 2H₂O

Question 18

Which of the following compounds will completely dissociate in water to form ions and conduct electricity?

Accepted Answer

Hydrogen chloride (HCl)

Answer

Acetic acid (CH₃COOH)

Answer

Ammonia (NH₃)

Answer

Sucrose (C₁₂H₂₂O₁₁)

Question 19

What is the pH of a 0.1 M solution of hydrochloric acid (HCl)?

Accepted Answer

1

Answer

3

Answer

7

Answer

10

Question 20

What is the defining characteristic that distinguishes strong electrolytes from weak electrolytes?

Accepted Answer

Degree of ionization: Strong electrolytes ionize completely, while weak electrolytes ionize partially.

Answer

Electrical conductivity: Strong electrolytes conduct electricity more efficiently.

Answer

Ion concentration: Weak electrolytes have a higher concentration of ions.

Answer

Acid-base nature: Strong electrolytes are always acids, while weak electrolytes are always bases.

Question 21

According to the law of conservation of mass, which quantity remains constant in a chemical reaction?

Accepted Answer

Total mass of reactants and products

Answer

Mass of reactants

Answer

Mass of products

Answer

Volume of reactants

Question 22

In a combination reaction, which of the following occurs?

Accepted Answer

Two or more substances form a single product

Answer

A single substance breaks down into two or more products

Answer

One element replaces another element in a compound

Answer

Two compounds exchange ions

Question 23

Calculate the molar mass of sodium chloride (NaCl) using its atomic masses: 22.99 g/mol for Na and 35.45 g/mol for Cl.

Accepted Answer

58.44 g/mol

Answer

22.99 g/mol

Answer

35.45 g/mol

Answer

61.34 g/mol

Question 24

Identify the redox reaction in the following options:

Accepted Answer

Electrolysis of water

Answer

Neutralization of an acid and a base

Answer

Precipitation of a salt from solution

Answer

Combustion of propane

Question 25

Which substance acts as a catalyst in chemical reactions?

Accepted Answer

Platinum

Answer

Sodium chloride

Answer

Iron(III) oxide

Answer

Sulfuric acid

Question 26

Write the rate law for a reaction that exhibits first-order dependence on both reactants A and B.

Accepted Answer

rate = k[A][B]

Answer

rate = k[A]

Answer

rate = k[A][B]^2

Answer

rate = k[A]^2[B]

Question 27

What is the enthalpy change for an endothermic reaction?

Accepted Answer

Positive

Answer

Negative

Answer

Zero

Answer

Cannot be determined

Question 28

What type of reaction is the following equation representing: Mg + 2HCl → MgCl2 + H2

Accepted Answer

Single displacement

Answer

Double displacement

Answer

Combustion

Answer

Neutralization

Question 29

What is the molarity of a solution containing 2 moles of solute in 4 liters of solution?

Accepted Answer

0.5 M

Answer

0.25 M

Answer

1.0 M

Answer

2.0 M

Question 30

Which of the following reactions is categorized as exothermic?

Accepted Answer

A reaction that releases heat

Answer

A reaction that absorbs heat

Answer

A reaction that occurs at a high temperature

Answer

A reaction that occurs at a low temperature

Question 31

In sodium chloride (NaCl), what is the mole ratio of sodium to chlorine?

Accepted Answer

1:1

Answer

1:2

Answer

2:1

Answer

2:2

Question 32

For an exothermic reaction, what is the sign of the enthalpy change (ΔH)?

Accepted Answer

Negative

Answer

Positive

Answer

Zero

Answer

Cannot be determined

Question 33

Which of the following factors does NOT influence the rate of a chemical reaction?

Accepted Answer

Magnetic field

Answer

Temperature

Answer

Concentration of reactants

Answer

Surface area of reactants

Question 34

Determine the oxidation number of nitrogen in nitric acid (HNO₃).

Accepted Answer

+5

Answer

+3

Answer

+1

Answer

-1

Question 35

Which of the following chemical equations is balanced?

Accepted Answer

2C₂H₆ + 7O₂ → 4CO₂ + 4H₂O

Answer

CH₄ + 2O → CO₂ + 2H₂O

Answer

2Na + Cl₂ → NaCl₂

Answer

Fe + 2HCl → FeCl + H₂

Question 36

Which of the following types of chemical reactions involve the combination of two or more reactants to form a single product?

Accepted Answer

Synthesis

Answer

Decomposition

Answer

Single displacement

Question 37

Which of the factors listed below does NOT influence the rate of a chemical reaction?

Accepted Answer

Volume of the container

Answer

Presence of a catalyst

Answer

Temperature

Answer

Concentration of reactants

Question 38

Identify the product formed in the following reaction: CH₄ + 2O₂ → ?

Accepted Answer

CO₂ + 2H₂O

Answer

CH₂O + H₂O

Answer

CO + 2H₂

Answer

C + 2H₂O

Question 39

Which of the following chemical equations is balanced correctly?

Accepted Answer

2Fe + 3Cl₂ → 2FeCl₃

Answer

Fe + Cl₂ → FeCl₂

Answer

FeCl₃ → Fe + 3Cl

Answer

2Fe + 2Cl₂ → 4FeCl

Question 40

Which of the following reactions is an example of a redox reaction?

Accepted Answer

Fe²⁺ + Cu²⁺ → Fe³⁺ + Cu⁺

Answer

NaOH + HCl → NaCl + H₂O

Answer

CO₂ + H₂O → H₂CO₃

Answer

C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂

Question 41

Which of the following is NOT a fundamental type of chemical reaction?

Accepted Answer

Condensation

Answer

Decomposition

Answer

Single displacement

Answer

Synthesis

Question 42

What is the mole ratio of aluminum to chlorine in the balanced chemical equation: 2Al + 3Cl2 -> 2AlCl3?

Accepted Answer

2:3

Answer

1:2

Answer

3:2

Answer

1:1

Question 43

Define activation energy in the context of a chemical reaction.

Accepted Answer

The minimum amount of energy that must be supplied to the reactants for the reaction to proceed.

Answer

The maximum amount of energy released during the reaction.

Answer

The energy required to break the bonds of the reactants.

Question 44

Identify the factors that can influence the rate of a chemical reaction.

Accepted Answer

Concentration of reactants, temperature, surface area of reactants, and presence of a catalyst

Answer

Concentration of reactants and temperature only

Answer

Surface area of reactants and presence of a catalyst only

Question 45

Explain the primary function of a catalyst in a chemical reaction.

Accepted Answer

To lower the activation energy of the reaction, allowing it to proceed more quickly.

Answer

To change the products of the reaction.

Answer

To increase the activation energy of the reaction, slowing it down.

Question 46

Which of the following reactions is an example of an acid-base neutralization reaction?

Accepted Answer

NaOH(aq) + HCl(aq) -> NaCl(aq) + H2O(l)

Answer

CH4(g) + 2O2(g) -> CO2(g) + 2H2O(g)

Answer

2Na(s) + 2H2O(l) -> 2NaOH(aq) + H2(g)

Question 47

What is the pH of a neutral solution at 25 degrees Celsius?

Accepted Answer

7

Answer

14

Answer

0

Answer

10

Question 48

Which of the following is a strong acid?

Accepted Answer

Hydrochloric acid (HCl)

Answer

Acetic acid (CH3COOH)

Answer

Ammonia (NH3)

Answer

Carbonic acid (H2CO3)