Question 1

A student is given a sample of an unknown white powder. Which experimental technique would be most appropriate to determine if the powder is a pure substance or a mixture?
Correct answer: Measuring its melting point and comparing it to a known value

Accepted Answer

Measuring its melting point and comparing it to a known value

Question 2

Which of the following best explains why metals are good conductors of electricity?
Correct answer: They have delocalized electrons that move freely throughout the structure

Accepted Answer

They have delocalized electrons that move freely throughout the structure

Question 3

A reaction vessel contains 10.0 g of calcium carbonate (CaCO₃) and produces 4.4 g of carbon dioxide (CO₂) upon heating. According to the law of conservation of mass, what is the total mass of the remaining products?
Correct answer: 5.6 g of calcium oxide (CaO)

Accepted Answer

5.6 g of calcium oxide (CaO)

Question 4

Which of the following is a correct application of the mole concept in a real-world context?
Correct answer: Calculating the amount of fertilizer needed for a field based on the number of moles of nitrogen required by the crops

Accepted Answer

Calculating the amount of fertilizer needed for a field based on the number of moles of nitrogen required by the crops

Question 5

A solution is prepared by dissolving 0.5 mol of NaCl in enough water to make 1.0 dm³ of solution. What is the concentration of NaCl in the solution?
Correct answer: 0.5 mol/dm³

Accepted Answer

0.5 mol/dm³

Question 6

Which of the following best describes the process of electrolysis in the context of environmental chemistry?
Correct answer: Using electricity to decompose water into hydrogen and oxygen gases, which can be used as clean fuels

Accepted Answer

Using electricity to decompose water into hydrogen and oxygen gases, which can be used as clean fuels

Question 7

A student mixes hydrochloric acid (HCl) with sodium hydroxide (NaOH) in a beaker. Which type of chemical reaction occurs, and what is the main product formed?
Correct answer: Neutralization; water

Accepted Answer

Neutralization; water

Question 8

Which of the following statements about the Periodic Table is correct?
Correct answer: Elements in the same group have similar chemical properties because they have the same number of outer electrons

Accepted Answer

Elements in the same group have similar chemical properties because they have the same number of outer electrons

Question 9

A chemist needs to prepare 250 cm³ of a 0.2 mol/dm³ NaOH solution. What mass of NaOH (M = 40 g/mol) is required?
Correct answer: 1.0 g

Accepted Answer

1.0 g

Question 10

Which of the following is an example of a real-world application of acids, bases, and salts?
Correct answer: Using baking soda (a base) to neutralize stomach acid in antacid tablets

Accepted Answer

Using baking soda (a base) to neutralize stomach acid in antacid tablets

Question 11

During a laboratory experiment, a student records the following data: initial mass of reactants = 12.0 g, final mass of products = 11.8 g. Which is the most likely explanation for the difference in mass?
Correct answer: A gas was produced and escaped during the reaction

Accepted Answer

A gas was produced and escaped during the reaction

Question 12

Which of the following best illustrates the importance of safe laboratory practice?
Correct answer: Wearing safety goggles to protect eyes from chemical splashes

Accepted Answer

Wearing safety goggles to protect eyes from chemical splashes

Question 13

Which of the following is a correct statement about organic chemistry?
Correct answer: It is the study of compounds containing carbon, often found in living organisms

Accepted Answer

It is the study of compounds containing carbon, often found in living organisms

Question 14

A student is asked to analyze a sample of river water for pollution. Which experimental technique would be most appropriate?
Correct answer: Chemical analysis using titration to determine the concentration of pollutants

Accepted Answer

Chemical analysis using titration to determine the concentration of pollutants

Question 15

Which of the following best describes the role of stoichiometry in industrial chemical processes?
Correct answer: It allows chemists to calculate the exact amounts of reactants needed to maximize product yield and minimize waste

Accepted Answer

It allows chemists to calculate the exact amounts of reactants needed to maximize product yield and minimize waste

Question 16

Which of the following is a correct statement about the environmental impact of metals?
Correct answer: Mining and refining metals can cause pollution and habitat destruction

Accepted Answer

Mining and refining metals can cause pollution and habitat destruction

Question 17

A student is given 24 g of magnesium (Mg, M = 24 g/mol) and reacts it completely with oxygen. How many moles of magnesium are present?
Correct answer: 1 mole

Accepted Answer

1 mole

Question 18

Which of the following best demonstrates the use of data analysis in chemistry?
Correct answer: Interpreting a graph of temperature change during a chemical reaction to determine the reaction's enthalpy change

Accepted Answer

Interpreting a graph of temperature change during a chemical reaction to determine the reaction's enthalpy change

Question 19

Which of the following is an ethical consideration in the application of chemistry to real-world problems?
Correct answer: Ensuring that chemical waste is disposed of safely to prevent environmental harm

Accepted Answer

Ensuring that chemical waste is disposed of safely to prevent environmental harm

Question 20

A student is asked to synthesize a salt in the laboratory. Which combination of reactants would be most appropriate?
Correct answer: Reacting an acid with a base

Accepted Answer

Reacting an acid with a base

Overview of Cambridge IGCSE Chemistry 0620 Syllabus

Study Guide - Practice Questions

Study Guide - Flashcards