Chemistry Comprehensive Practice Test 3

Questions

100

Marks

Sections

100%

Auto-Graded

Section	Questions	Marks Each	Total
A — Multiple Choice	15	2	30
B — True / False	10	2	20
C — Fill in the Blank	10	2	20
D — Column Matching	5 sub-questions	2	10
E — Short Answer	5	4	20
Total	45	—	100

Source scope: This paper covers the 12 Chemistry articles currently in the EDUSAMBAM master library: Acids, Bases and Salts: The Chemistry of Sour, Bitter, and Neutral; Atoms and the Periodic Table: The Building Blocks of Everything; Chemical Bonding: How Atoms Connect to Form Everything; Chemical Reactions and Equations: The Language of Change; Chemistry in Everyday Life: The Science Hiding in Plain Sight; Electrochemistry: Where Chemistry Meets Electricity; Chemistry of Metals and Non-Metals: A Tale of Two Families; Mixtures and Solutions: How Substances Combine Without Reacting; The Mole and Chemical Calculations: Counting the Uncountable; Organic Chemistry Basics: The Chemistry of Carbon; States of Matter and Changes: Why Substances Transform; What is Chemistry? The Science of Matter and Change. Questions progress from basic concepts to intermediate application and advanced reasoning.

Section A — Multiple Choice

30 marks

15 questions · 2 marks each. Select the best answer.

1.A solution with pH 3 is:Basic2 pts

A. Strongly acidic

B. Neutral

C. Weakly basic

D. Strongly basic

2.Which method is most suitable for separating an insoluble solid from a liquid?Basic2 pts

A. Filtration

B. Distillation

C. Chromatography

D. Sublimation

3.One mole contains approximately:Intermediate2 pts

A. 6.02 × 10²³ particles

B. 9.81 × 10² particles

C. 3.00 × 10⁸ particles

D. 1.60 × 10⁻¹⁹ particles

4.Oxidation at an electrode occurs at the:Intermediate2 pts

A. Cathode

B. Anode

C. Salt bridge only

D. Electrolyte surface only

5.Which property is typical of metals?Basic2 pts

A. Poor electrical conductivity

B. Brittleness in all forms

C. Malleability

D. Lack of lustre

6.Which functional group identifies an alcohol?Intermediate2 pts

A. –COOH

B. –OH

C. –CHO

D. –CO–

7.At constant pressure, heating a liquid generally causes its particles to:Basic2 pts

A. Lose all motion

B. Gain kinetic energy

C. Become neutrons

D. Stop colliding

8.If 2 mol of H₂ react completely with O₂ according to 2H₂ + O₂ → 2H₂O, how many moles of H₂O form?Intermediate2 pts

A. 1

B. 2

C. 3

D. 4

9.Which statement best explains why catalysts speed many reactions?Advanced2 pts

A. They permanently increase product energy

B. They provide an alternative pathway with lower activation energy

C. They change the equilibrium constant in every reaction

D. They are consumed as reactants

10.Which salt is formed when hydrochloric acid reacts with sodium hydroxide?Basic2 pts

A. Sodium sulfate

B. Sodium chloride

C. Sodium carbonate

D. Sodium nitrate

11.Which element has the electron configuration 2,8,1?Intermediate2 pts

A. Sodium

B. Magnesium

C. Chlorine

D. Neon

12.A covalent bond involves:Basic2 pts

A. Sharing of electron pairs

B. Transfer of neutrons

C. Sharing of protons

D. Loss of the nucleus

13.Which factor generally increases the rate of a reaction?Intermediate2 pts

A. Lower temperature

B. Lower concentration

C. Higher temperature

D. Removing all collisions

14.Which technique separates coloured substances based on different movement through a medium?Basic2 pts

A. Filtration

B. Chromatography

C. Decantation

D. Evaporation

15.In a redox reaction, reduction can be described as:Advanced2 pts

A. Loss of electrons

B. Gain of electrons

C. Gain of neutrons

D. Loss of protons from the nucleus

Section B — True / False

20 marks

10 questions · 2 marks each. Choose True or False.

16.The periodic table arranges elements by increasing atomic number.Basic2 pts

True

False

17.A chemical equation may be balanced by changing subscripts in formulas.Advanced2 pts

True

False

18.Evaporation occurs only at the boiling point.Basic2 pts

True

False

19.A solute is the substance that is dissolved in a solution.Basic2 pts

True

False

20.Reduction can involve gain of electrons.Intermediate2 pts

True

False

21.The anode is always negatively charged in every type of electrochemical cell.Advanced2 pts

True

False

22.Diamond and graphite are forms of carbon with different structures and properties.Advanced2 pts

True

False

23.A physical change does not normally create a new substance.Basic2 pts

True

False

24.A strong acid is necessarily concentrated.Advanced2 pts

True

False

25.Reaction rate can be affected by concentration and temperature.Intermediate2 pts

True

False

Section C — Fill in the Blank

20 marks

10 questions · 2 marks each. Type the missing term or value.

26.A solution with pH 7 at 25 °C is approximately ______.Basic2 pts

27.The vertical columns in the periodic table are called ______.Basic2 pts

28.A substance made of two or more elements chemically combined is a ______.Basic2 pts

29.The starting substances in a chemical reaction are called ______.Basic2 pts

30.The minimum energy needed for an effective reaction is called ______ energy.Intermediate2 pts

31.A homogeneous mixture of solute and solvent is a ______.Basic2 pts

32.The formula relating amount of substance to molar mass is n = m / ______.Advanced2 pts

33.In a galvanic cell, electrons travel through the external circuit from the ______ to the cathode.Advanced2 pts

34.The simplest saturated hydrocarbons are called ______.Intermediate2 pts

35.The direct change from gas to solid is called ______.Intermediate2 pts

Section D — Matching

10 marks

5 sub-questions · 2 marks each. Match each sub-question in Column A with the correct entry in Column B.

36.Match each term in Column A with the correct description in Column B.Advanced10 pts

Column A

36(a). Atomic number

36(b). Filtration

36(c). Activation energy

36(d). Oxidation

36(e). Saturated solution

Column B

Activation energy

Oxidation

Saturated solution

Atomic number

Filtration

Section E — Short Answer

20 marks

5 questions · 4 marks each. Answer in one or two clear sentences.

41.What is meant by a balanced chemical equation?Basic4 pts

42.Describe one difference between ionic and covalent bonding.Basic4 pts

43.How does filtration differ from distillation?Intermediate4 pts

44.Why is the mole useful in chemical calculations?Intermediate4 pts

45.Explain why a strong acid is not necessarily a concentrated acid.Advanced4 pts