Chemical Reactions: Dive into the World of Chemical Transformations

Question 1

Which of the following is a limiting reactant?

Accepted Answer

Reactant that is completely consumed first

Answer

Reactant that is present in excess

Answer

Reactant with the highest molar mass

Answer

Reactant with the lowest molar mass

Question 2

The conjugate acid of H2O is:

Accepted Answer

H3O+

Answer

OH-

Answer

H+

Answer

O2-

Question 3

Which of the following is a strong electrolyte?

Accepted Answer

NaCl

Answer

CH3OH

Answer

NH3

Answer

C6H12O6

Question 4

The process by which a metal loses electrons is called:

Accepted Answer

Oxidation

Answer

Reduction

Answer

Ionization

Answer

Neutralization

Question 5

In a combustion reaction, which reactant is always present?

Accepted Answer

Oxygen

Answer

Hydrogen

Answer

Carbon

Answer

Nitrogen

Question 6

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

Accepted Answer

Shape of the reaction container

Answer

Temperature

Answer

Concentration of reactants

Answer

Presence of a catalyst

Question 7

What is the balanced chemical equation for the reaction between sodium and chlorine?

Accepted Answer

2Na + Cl2 → 2NaCl

Answer

Na + Cl → NaCl

Answer

2Na + 2Cl → NaCl2

Answer

Na + Cl2 → Na2Cl

Question 8

Which of the following is a redox reaction?

Accepted Answer

Combustion of methane

Answer

Neutralization of an acid and a base

Answer

Dissolution of salt in water

Answer

Decomposition of hydrogen peroxide

Question 9

Which of the following is a strong acid?

Accepted Answer

Hydrochloric acid

Answer

Acetic acid

Answer

Carbonic acid

Answer

Phosphoric acid

Question 10

What is the hybridization of the carbon atom in methane?

Accepted Answer

sp3

Answer

sp

Answer

sp2

Answer

dsp3

Question 11

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

Accepted Answer

Filtration

Answer

Decomposition

Answer

Synthesis

Answer

Precipitation

Question 12

Which term accurately describes a chemical reaction wherein two or more elements or compounds coalesce to form a single new product?

Accepted Answer

Synthesis reaction

Answer

Decomposition reaction

Answer

Displacement reaction

Answer

Redox reaction

Question 13

Identify the reaction type that involves a transfer of electrons between reactants:

Accepted Answer

Redox reaction

Answer

Neutralization reaction

Answer

Precipitation reaction

Answer

Acid-base reaction

Question 14

Which of the following is NOT a type of chemical reaction we have studied in this unit?

Accepted Answer

Nuclear reaction

Answer

Combination reaction

Answer

Decomposition reaction

Answer

Neutralization reaction

Question 15

Which of the following is **not** a recognized type of chemical reaction?

Accepted Answer

Conservation

Answer

Combination

Answer

Decomposition

Answer

Single-replacement

Question 16

In a combustion reaction, what is the reactant that is consumed?

Accepted Answer

Fuel

Answer

Oxygen

Answer

Water

Answer

Carbon dioxide

Question 17

Which of the following is an example of an exothermic reaction?

Accepted Answer

Burning of gasoline

Answer

Dissolving salt in water

Answer

Freezing of water

Answer

Rusting of iron

Question 18

Which of the following functional groups is present in an alcohol?

Accepted Answer

-OH

Answer

-COOH

Answer

-NH2

Answer

-C=O

Question 19

Which of the following is a type of chemical reaction that involves the combination of two or more substances to form a new substance?

Accepted Answer

Combination

Answer

Decomposition

Answer

Fusion

Answer

Double displacement

Question 20

In a balanced chemical equation, the coefficients in front of the reactants and products represent the:

Accepted Answer

Number of moles of each substance

Answer

Number of atoms of each element

Answer

Number of molecules of each substance

Answer

Mass of each substance

Question 21

In an exothermic reaction, energy is:

Accepted Answer

Released

Answer

Absorbed

Answer

Conserved

Answer

Neither released nor absorbed

Question 22

In a neutralization reaction, an acid and a base react to form:

Accepted Answer

Salt and water

Answer

Salt and gas

Answer

Water and gas

Answer

Base and water

Question 23

Which of the following is a redox reaction?

Accepted Answer

Fe2O3 + 3H2 → 2Fe + 3H2O

Answer

2Na + Cl2 → 2NaCl

Answer

NaOH + HCl → NaCl + H2O

Answer

NH3 + HCl → NH4Cl

Question 24

The equilibrium constant (Keq) of a reaction is a measure of:

Accepted Answer

The relative amounts of reactants and products at equilibrium

Answer

The extent to which the reaction proceeds in the forward direction

Answer

The extent to which the reaction proceeds in the reverse direction

Answer

The change in free energy of the reaction

Question 25

Which of the following is an example of a catalyst?

Accepted Answer

Platinum

Answer

Sodium chloride

Answer

Hydrochloric acid

Answer

Water

Question 26

How does the equilibrium constant reveal the tendency of a chemical reaction to proceed spontaneously?

Accepted Answer

A higher equilibrium constant indicates a spontaneous shift towards product formation.

Answer

A lower equilibrium constant suggests a spontaneous preference for reactants.

Answer

The spontaneity of a reaction is independent of its equilibrium constant.

Question 27

What are two defining characteristics of chemical reactions?

Accepted Answer

Release or absorption of energy and formation of new substances

Answer

Formation of new substances and change in color

Answer

Change in temperature and release or absorption of energy

Answer

Formation of new substances and change in temperature

Question 28

In what type of reaction do two or more substances combine to form one product?

Accepted Answer

Synthesis

Answer

Decomposition

Answer

Single displacement

Answer

Double displacement

Question 29

What is the primary function of a catalyst in a chemical reaction?

Accepted Answer

To decrease the activation energy of the reaction

Answer

To increase the activation energy of the reaction

Answer

To change the products of the reaction

Answer

To stop the reaction from occurring

Question 30

Which of the following is an example of an endothermic reaction?

Accepted Answer

Melting of ice

Answer

Combustion of gasoline

Answer

Freezing of water

Answer

Evaporation of alcohol

Question 31

What is the hybridization of the central carbon atom in methane?

Accepted Answer

sp³

Answer

sp

Answer

sp²

Answer

sp³d

Question 32

Which of the following molecules is polar?

Accepted Answer

H₂O

Answer

CO₂

Answer

CH₄

Answer

N₂

Question 33

Explain how chemical reactions have had a transformative impact on various industries through their practical applications.

Accepted Answer

Production of synthetic materials like plastics and composites

Accepted Answer

Preservation of food items through methods like canning

Accepted Answer

Purification of water in treatment facilities using chemical processes

Answer

Natural photosynthesis in plants, converting sunlight into energy

Question 34

Analyze the chemical reaction: 2H2 + O2 → 2H2O. Determine the type of reaction it exemplifies.

Accepted Answer

Synthesis

Answer

Decomposition

Answer

Single-displacement

Answer

Double-displacement

Question 35

Identify the option that does NOT represent a recognized type of chemical reaction.

Accepted Answer

Nuclear reaction

Answer

Combination reaction

Answer

Decomposition reaction

Answer

Precipitation reaction

Question 36

Which option is NOT a type of chemical reaction?

Accepted Answer

Inflation

Answer

Single displacement

Answer

Combustion

Answer

Decomposition

Question 37

In a balanced chemical equation, the coefficients in front of the reactants and products represent the:

Accepted Answer

Mole ratios

Answer

Volume ratios

Answer

Energy ratios

Answer

Mass ratios

Question 38

Which factor listed below can affect the rate of a chemical reaction?

Accepted Answer

Temperature

Answer

Color of reactants

Answer

Shape of reactants

Answer

Age of reactants

Question 39

The process of breaking down a compound into simpler substances is known as:

Accepted Answer

Decomposition

Answer

Single replacement

Answer

Synthesis

Answer

Combustion

Question 40

In a double displacement reaction, the:

Accepted Answer

Cations and anions of the reactants switch places.

Answer

Products are always gases.

Answer

Elements of the reactants switch places.

Answer

Reactants combine to form a single product.

Question 41

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

Accepted Answer

Acid + Base → Salt + Water

Answer

Fuel + Oxygen → Carbon dioxide + Water

Answer

Water + Carbon dioxide → Carbonic acid

Answer

Metal + Non-metal → Ionic compound

Question 42

The chemical equation for the complete combustion of methane is:

Accepted Answer

CH₄ + 2O₂ → CO₂ + 2H₂O

Answer

CH₄ + O₂ → CO + 2H₂O

Answer

CH₄ + 2O₂ → 2CO + 2H₂

Answer

CH₄ + O₂ → C + 2H₂O

Question 43

Which of the reactions listed below is a redox reaction?

Accepted Answer

Fe + 2HCl → FeCl₂ + H₂

Answer

2Na + Cl₂ → 2NaCl

Answer

NaCl + AgNO₃ → AgCl + NaNO₃

Answer

CH₄ + 2O₂ → CO₂ + 2H₂O

Question 44

Which of the following is a fundamental characteristic of a chemical reaction?

Accepted Answer

Change in the composition of substances involved

Answer

Complete conversion of reactants into products

Answer

Change in total mass of involved substances

Answer

No formation of new substances

Question 45

Identify the type of chemical reaction represented by the equation: AB + CD → AC + BD:

Accepted Answer

Double displacement

Answer

Single displacement

Answer

Decomposition

Answer

Combination

Question 46

In a chemical reaction, what is the role of a catalyst?

Accepted Answer

Reduces the activation energy

Answer

Behaves as a reactant in the reaction

Answer

Provides energy for the reaction

Answer

Increases the number of collisions between reactants

Question 47

Which of the following reactions is an example of an endothermic reaction?

Accepted Answer

Melting of ice

Answer

Rusting of iron

Answer

Burning of wood

Answer

Dissolution of salt in water

Question 48

Which of the following observations is categorized as qualitative in a chemical reaction?

Accepted Answer

Change in color

Answer

Mass of reactants

Answer

Equilibrium constant of the reaction

Answer

Moles of products formed

Question 49

Regarding methane (CH₄), what is the hybridization of its carbon atom?

Accepted Answer

sp³

Answer

sp³d

Answer

sp

Answer

sp²