Question 1

A student is asked to determine the purity of a sample of copper(II) sulfate by dissolving it in water and titrating it with sodium hydroxide. Which of the following best describes the type of skill being assessed in this experiment?
Correct answer: Application of safe laboratory practice and data analysis

Accepted Answer

Application of safe laboratory practice and data analysis

Question 2

Which of the following best explains why ice floats on water, based on the states of matter and particle arrangement?
Correct answer: Ice is less dense than liquid water because its particles are arranged in a lattice with more space between them

Accepted Answer

Ice is less dense than liquid water because its particles are arranged in a lattice with more space between them

Question 3

A chemist needs to prepare 250 mL of a 0.2 mol/dm³ NaCl solution. The molar mass of NaCl is 58.5 g/mol. How many grams of NaCl are required?
Correct answer: 2.93 g

Accepted Answer

2.93 g

Question 4

Which of the following is a correct statement about the differences between elements, compounds, and mixtures?
Correct answer: Compounds consist of two or more elements chemically combined in fixed ratios

Accepted Answer

Compounds consist of two or more elements chemically combined in fixed ratios

Question 5

During the electrolysis of molten lead(II) bromide, which products are formed at the electrodes?
Correct answer: Bromine at the anode and lead at the cathode

Accepted Answer

Bromine at the anode and lead at the cathode

Question 6

A student mixes hydrochloric acid with sodium hydroxide in a beaker. The temperature of the solution increases. Which type of reaction is this, and what does the temperature change indicate?
Correct answer: Exothermic reaction; energy is released

Accepted Answer

Exothermic reaction; energy is released

Question 7

Which of the following best describes the role of a catalyst in a chemical reaction?
Correct answer: It lowers the activation energy, increasing the rate of reaction

Accepted Answer

It lowers the activation energy, increasing the rate of reaction

Question 8

A solution has a pH of 3. Which of the following statements is correct?
Correct answer: The solution is acidic

Accepted Answer

The solution is acidic

Question 9

Which of the following best explains why noble gases are generally unreactive?
Correct answer: They have a full outer electron shell, making them stable

Accepted Answer

They have a full outer electron shell, making them stable

Question 10

Iron rusts when exposed to air and moisture. Which of the following best describes the type of chemical reaction involved?
Correct answer: Oxidation

Accepted Answer

Oxidation

Question 11

Which of the following is a major environmental concern associated with the combustion of fossil fuels?
Correct answer: Release of carbon dioxide leading to global warming

Accepted Answer

Release of carbon dioxide leading to global warming

Question 12

Which of the following is a correct statement about alkanes in organic chemistry?
Correct answer: Alkanes are saturated hydrocarbons with only single bonds

Accepted Answer

Alkanes are saturated hydrocarbons with only single bonds

Question 13

A student is given a colorless solution and asked to identify the presence of chloride ions. Which experimental technique should be used?
Correct answer: Add silver nitrate solution; a white precipitate indicates chloride ions

Accepted Answer

Add silver nitrate solution; a white precipitate indicates chloride ions

Question 14

Which of the following best describes the difference between a strong acid and a weak acid?
Correct answer: A strong acid ionizes completely in water, while a weak acid only partially ionizes

Accepted Answer

A strong acid ionizes completely in water, while a weak acid only partially ionizes

Question 15

A 10.0 g sample of calcium carbonate (CaCO₃, molar mass = 100 g/mol) is heated strongly. How many moles of carbon dioxide (CO₂) are produced?
Correct answer: 0.10 mol

Accepted Answer

0.10 mol

Question 16

Which of the following is the best example of a transfer of skills from chemistry to a real-world context?
Correct answer: Applying knowledge of acids and bases to treat acid indigestion

Accepted Answer

Applying knowledge of acids and bases to treat acid indigestion

Question 17

Which of the following best describes the process of fractional distillation?
Correct answer: Separation of liquids with different boiling points by repeated vaporization and condensation

Accepted Answer

Separation of liquids with different boiling points by repeated vaporization and condensation

Question 18

A student is asked to balance the following equation: __Al + __O₂ → __Al₂O₃. What are the correct coefficients?
Correct answer: 4, 3, 2

Accepted Answer

4, 3, 2

Question 19

Which of the following is a correct safety precaution when heating a substance in a test tube?
Correct answer: Point the open end of the test tube away from yourself and others

Accepted Answer

Point the open end of the test tube away from yourself and others

Question 20

Which of the following best describes the trend in reactivity of Group 1 metals as you go down the group?
Correct answer: Reactivity increases because the outer electron is more easily lost

Accepted Answer

Reactivity increases because the outer electron is more easily lost

Overview of Cambridge IGCSE Chemistry 0620 Syllabus

Study Guide - Practice Questions

Study Guide - Flashcards