Question 1

Which of the following best explains why ionic compounds generally have high melting points?
Correct answer: The strong electrostatic attraction between oppositely charged ions requires a large amount of energy to overcome.

Accepted Answer

The strong electrostatic attraction between oppositely charged ions requires a large amount of energy to overcome.

Question 2

A student is asked to separate a mixture of sand and salt. Which sequence of experimental techniques should they use to obtain pure salt?
Correct answer: Dissolve in water, filter, evaporate the filtrate.

Accepted Answer

Dissolve in water, filter, evaporate the filtrate.

Question 3

Which of the following statements about isotopes is correct?
Correct answer: Isotopes of an element have the same chemical properties but different physical properties.

Accepted Answer

Isotopes of an element have the same chemical properties but different physical properties.

Question 4

A sample of chlorine contains 75% 35Cl (atomic mass = 35) and 25% 37Cl (atomic mass = 37). What is the relative atomic mass (Ar) of chlorine?
Correct answer: 35.5

Accepted Answer

35.5

Question 5

Which of the following best describes the process of diffusion in gases?
Correct answer: Particles move randomly and spread out to fill the available space due to their kinetic energy.

Accepted Answer

Particles move randomly and spread out to fill the available space due to their kinetic energy.

Question 6

A metal X reacts with dilute hydrochloric acid to produce a colorless gas and a solution of X chloride. Which property of X is being demonstrated in this reaction?
Correct answer: X is above hydrogen in the reactivity series.

Accepted Answer

X is above hydrogen in the reactivity series.

Question 7

Which of the following is a correct statement about acids and bases?
Correct answer: Acids donate protons and bases accept protons.

Accepted Answer

Acids donate protons and bases accept protons.

Question 8

During an experiment, a student observes that a white solid forms when solutions of silver nitrate and sodium chloride are mixed. What type of reaction has occurred?
Correct answer: Precipitation reaction

Accepted Answer

Precipitation reaction

Question 9

Which of the following best explains why graphite conducts electricity but diamond does not?
Correct answer: Graphite has delocalized electrons between its layers, while diamond has all electrons involved in covalent bonds.

Accepted Answer

Graphite has delocalized electrons between its layers, while diamond has all electrons involved in covalent bonds.

Question 10

A student is asked to design an experiment to determine the effect of temperature on the rate of a chemical reaction. Which variable should be kept constant to ensure a fair test?
Correct answer: The concentration of the reactants

Accepted Answer

The concentration of the reactants

Question 11

Which of the following is a correct balanced equation for the reaction between sodium and water?
Correct answer: 2Na + 2H2O → 2NaOH + H2

Accepted Answer

2Na + 2H2O → 2NaOH + H2

Question 12

Which of the following best describes the environmental impact of burning fossil fuels?
Correct answer: It releases greenhouse gases such as carbon dioxide, contributing to global warming.

Accepted Answer

It releases greenhouse gases such as carbon dioxide, contributing to global warming.

Question 13

Which statement about the Periodic Table is correct?
Correct answer: Elements in the same group have the same number of outer electrons.

Accepted Answer

Elements in the same group have the same number of outer electrons.

Question 14

A solution turns blue litmus paper red and reacts with magnesium to produce hydrogen gas. What type of solution is this?
Correct answer: An acidic solution

Accepted Answer

An acidic solution

Question 15

Which of the following is a property of metals explained by metallic bonding?
Correct answer: Electrical conductivity due to delocalized electrons

Accepted Answer

Electrical conductivity due to delocalized electrons

Question 16

A chemist needs to determine the purity of a sample of aspirin. Which technique would be most appropriate?
Correct answer: Chromatography

Accepted Answer

Chromatography

Question 17

Which of the following best describes a redox reaction?
Correct answer: A reaction involving the transfer of electrons between species.

Accepted Answer

A reaction involving the transfer of electrons between species.

Question 18

Which of the following is a correct statement about covalent compounds?
Correct answer: They are formed by the sharing of electrons between nonmetals.

Accepted Answer

They are formed by the sharing of electrons between nonmetals.

Question 19

A student is investigating the electrolysis of copper(II) sulfate solution using copper electrodes. What observation would indicate that the mass of the anode decreases during the experiment?
Correct answer: Copper is deposited on the cathode.

Accepted Answer

Copper is deposited on the cathode.

Question 20

Which of the following best explains why water is a good solvent for ionic compounds?
Correct answer: Water molecules are polar and can surround and separate ions.

Accepted Answer

Water molecules are polar and can surround and separate ions.

Overview of Cambridge IGCSE Chemistry 0620 Syllabus

Study Guide - Practice Questions

Study Guide - Flashcards