Chemistry 0620 · IGCSE
Physical and chemical changes
100 practice questions on Physical and chemical changes, with worked solutions and instant marking.
Water is introduced to hydrated copper(II) sulfate. What colour change is observed?
Feb/March 2017
Two reactions, X and Y, produce carbon dioxide. $\text{CH}_4 \xrightarrow{X} \text{CO}_2 \xleftarrow{Y} \text{CaCO}_3$ What types of reaction are X and Y?
Feb/March 2017
Two reactions, X and Y, form carbon dioxide. $\text{CH}_4 \xrightarrow{X} \text{CO}_2 \xleftarrow{Y} \text{CaCO}_3$ What kinds of reaction are X and Y?
Feb/March 2017
Which process is associated with a chemical change?
Feb/March 2019
Which change counts as a physical change?
Feb/March 2020
The diagram illustrates the transformation of an anhydrous salt into its hydrated form. Which statement is correct?
Feb/March 2020
Which change counts as a physical change?
Feb/March 2020
Which row gives a description of a chemical change?
Feb/March 2023
Methane, $\text{CH}_4$, burns in air and produces carbon dioxide plus water. What is the balanced equation for this reaction?
Feb/March 2023
When calcium carbonate is heated strongly, carbon dioxide gas is given off. Which words describe the kind of change that takes place?
Feb/March 2024
Which of the following lists includes only chemical changes?
Feb/March 2024
Which statement is true of both physical and chemical changes?
Feb/March 2025
Which of these changes is a physical change?
Feb/March 2025
If limestone is heated, it produces lime (calcium oxide) and carbon dioxide. $\text{CaCO}_3(s) \rightarrow \text{CaO}(s) + \text{CO}_2(g)$ Which statement is not correct?
May/June 2016
In which reaction does the colour change from blue to white?
May/June 2016
What process is used to produce lime (calcium oxide) from limestone (calcium carbonate)?
May/June 2016
Certain magnesium compounds break down on heating. What products are formed when magnesium nitrate, $\text{Mg(NO}_3)_2$, and magnesium hydroxide, $\text{Mg(OH)}_2$, undergo thermal decomposition?
May/June 2016
What process is used to produce lime (calcium oxide) from limestone (calcium carbonate)?
May/June 2016
When sulfur is heated, it undergoes a \(\ldots\ldots 1 \ldots\ldots\) change as it melts. If heating continues, the sulfur then undergoes a \(\ldots\ldots 2 \ldots\ldots\) change and produces sulfur dioxide. Which words fill gaps 1 and 2?
May/June 2017
During which process is carbon dioxide not produced?
May/June 2017
When calcium carbonate is heated, a gas is formed. What kind of change is this?
May/June 2017
Which of these changes are physical changes?
May/June 2017
During which process is carbon dioxide not produced?
May/June 2017
Two equations are given. reaction 1: $\text{CaCO}_3 \rightarrow \text{CaO} + \text{CO}_2$ reaction 2: $\text{CaO} + \text{H}_2\text{O} \rightarrow \text{Ca(OH)}_2$ Which terms are used for reactions 1 and 2?
May/June 2017
When sulfur is heated, it changes by a ……1…… process as it melts. If heating continues, the sulfur changes by a ……2…… process and sulfur dioxide is formed. Which words fill gaps 1 and 2?
May/June 2017
Keratin is a protein present in human hair. A chemical breakdown of keratin produces amino acids. What is the name of this chemical process?
May/June 2017
A gas is formed on heating calcium carbonate. What type of change is this?
May/June 2017
Which of the following are physical changes?
May/June 2017
Two equations are presented. reaction 1: $\text{CaCO}_3 \rightarrow \text{CaO} + \text{CO}_2$ reaction 2: $\text{CaO} + \text{H}_2\text{O} \rightarrow \text{Ca(OH)}_2$ Which terms are used to describe reactions 1 and 2?
May/June 2017
Water is added to anhydrous copper(II) sulfate. What occurs during the reaction?
May/June 2018
What process is used to turn limestone (calcium carbonate) into lime?
May/June 2018
Which of the following statements about chemical reactions is correct?
May/June 2018
During a chemical reaction, the blue compound $X$ was converted into the white compound $Y$. $X \rightarrow Y$ Which statement best describes this reaction?
May/June 2018
Limestone is a useful material with a wide range of uses. When limestone is heated, ........1....... and carbon dioxide are formed. This reaction is known as ........2....... Which words correctly fill gaps 1 and 2?
May/June 2018
What process is used to change limestone (calcium carbonate) into lime?
May/June 2018
Limestone is a valuable material that has many different uses. When limestone is heated, ........1........ and carbon dioxide are produced. The reaction is known as ........2........ . Which words correctly fill gaps 1 and 2?
May/June 2018
Which process counts as a physical change?
May/June 2019
The diagram shows a lime kiln that is used to heat limestone to a very high temperature. What comes out of the kiln at X?
May/June 2019
Which process counts as a physical change?
May/June 2019
When blue-green crystals of nickel(II) sulfate are heated, water is given off and a yellow solid is left behind. If water is then added to the yellow solid, the blue-green colour comes back. Which process describes these changes?
May/June 2019
The diagram shows a lime kiln that is used to heat limestone to a very high temperature. What exits the kiln at X?
May/June 2019
Which row shows the changes that happen when metals burn in oxygen?
May/June 2019
Which process counts as a physical change?
May/June 2019
If blue-green crystals of nickel(II) sulfate are heated, water is released and a yellow solid is left behind. When water is then added to the yellow solid, the blue-green colour returns. Which process name is used for these changes?
May/June 2019
The diagram shows a lime kiln that is used to heat limestone to a very high temperature. What comes out of the kiln at X?
May/June 2019
When nickel(II) sulfate crystals that are blue-green are heated, water is given off and a yellow solid is left behind. If water is then added to this yellow solid, the blue-green colour comes back. What process is shown by these changes?
May/June 2019
The diagram shows a lime kiln that is used to heat limestone to a very high temperature. What comes out of the kiln at X?
May/June 2019
A student warmed the carbonates and nitrates of sodium and copper. The outcomes are shown. Which rows give the correct outcomes?
May/June 2019
When blue-green crystals of nickel(II) sulfate are heated, water is released and a yellow solid is left behind. If water is then added to the yellow solid, the blue-green colour returns. What process name describes these changes?
May/June 2019
When heated, magnesium nitrate, magnesium hydroxide and magnesium carbonate each decompose. Which statement regarding these decomposition reactions is correct?
May/June 2019
The diagram shows a lime kiln that is used to heat limestone to a very high temperature. What is released from the kiln at X?
May/June 2019
Heating sulfur first causes a ......1...... change when it melts. If heating continues, sulfur then undergoes a ......2...... change, producing sulfur dioxide. Which words should be used in gaps 1 and 2?
May/June 2021
Methane reacts with oxygen when it burns, producing carbon dioxide and water. What is the balanced equation for this reaction?
May/June 2021
When sulfur is heated, it experiences a ......1...... change as it melts. If heating continues, the sulfur then undergoes a ......2...... change and produces sulfur dioxide. Which words fill gaps 1 and 2?
May/June 2021
As sulfur is heated, it first experiences a .....1..... change as it melts. If heating continues, the sulfur then undergoes a .....2..... change and produces sulfur dioxide. Which words fill gaps 1 and 2?
May/June 2021
Hydrated copper(II) sulfate is blue. On heating, it produces white anhydrous copper(II) sulfate. How can a sample of anhydrous copper(II) sulfate be converted into hydrated copper(II) sulfate?
May/June 2021
When sulfur is heated, it experiences a .....1..... change as it melts. If heating continues, the sulfur then undergoes a .....2..... change and produces sulfur dioxide. Which words fill gaps 1 and 2?
May/June 2021
When sulfur is heated, it experiences a ....1.... change as it melts. If heating continues, the sulfur then undergoes a ....2.... change and produces sulfur dioxide. Which words fill gaps 1 and 2?
May/June 2021
When sulfur is heated, it experiences a .....1..... change as it melts. If heating continues, the sulfur then undergoes a .....2..... change and produces sulfur dioxide. Which words correctly fill gaps 1 and 2?
May/June 2021
Which row shows a chemical change and a physical change?
May/June 2022
Water is added to anhydrous copper(II) sulfate. What occurs during the reaction?
May/June 2022
Which products are formed when limestone (calcium carbonate) is strongly heated?
May/June 2022
What type of reaction takes place when calcium carbonate is heated to a high temperature and forms calcium oxide and carbon dioxide?
May/June 2022
Which row shows a chemical change and a physical change?
May/June 2022
Water is added to anhydrous copper(II) sulfate. What occurs during this reaction?
May/June 2022
What products are formed when limestone (calcium carbonate) is heated strongly?
May/June 2022
Which row shows a chemical change and a physical change?
May/June 2022
Water is mixed with anhydrous copper(II) sulfate. What occurs during the reaction?
May/June 2022
Which products are formed when limestone (calcium carbonate) is heated strongly?
May/June 2022
Which row correctly shows a chemical change and a physical change?
May/June 2022
Water is introduced to anhydrous copper(II) sulfate. What occurs during the reaction?
May/June 2022
Which products are formed when limestone (calcium carbonate) is heated strongly?
May/June 2022
Which row shows a chemical change and a physical change?
May/June 2022
Water is introduced to anhydrous copper(II) sulfate. What occurs during the reaction?
May/June 2022
A Bunsen burner is used to heat three metal compounds, J, K and L. The outcomes are shown. Which row correctly identifies J, K and L?
May/June 2022
What products are formed when limestone (calcium carbonate) is strongly heated?
May/June 2022
Which row shows a chemical change and a physical change?
May/June 2022
Water is introduced to anhydrous copper(II) sulfate. What takes place during the reaction?
May/June 2022
When limestone (calcium carbonate) is heated strongly, what products are formed?
May/June 2022
Solid copper(II) sulfate can be found in two forms, anhydrous and hydrated. One of these forms is blue, whereas the other is white. The change between the two forms can be reversed. blue form $\rightleftharpoons$ white form Which form is the blue form, and by what method is the change from the blue form to the white form caused?
May/June 2023
When a student heats hydrated copper(II) sulfate, the blue crystals turn into a white powder. What should the student do to change it back?
May/June 2023
Solid copper(II) sulfate can exist in two forms: anhydrous and hydrated. One of the forms is blue, while the other is white. The conversion between these two forms is reversible. blue form $\rightleftharpoons$ white form Which form is blue, and how can the blue form be changed into the white form?
May/June 2023
Which equation shows a chemical change?
May/June 2023
A student heats hydrated copper(II) sulfate. The blue crystals turn into a white powder. How can the student make this reaction go back the other way?
May/June 2023
A set of symbol equations and word equations, labelled A to J, is given below. A Fe$^{3+}$ + 3OH$^-$ $\rightarrow$ Fe(OH)$__3$ B H$^+$ + OH$^-$ $\rightarrow$ H$__2$O C ethane + chlorine $\rightarrow$ chloroethane + hydrogen chloride D C$__{12}$H$__{26}$ $\rightarrow$ C$__8$H$__{18}$ + C$__4$H$__8$ E ethene + steam $\rightarrow$ ethanol F chlorine + aqueous potassium iodide $\rightarrow$ iodine + aqueous potassium chloride G C$__6$H$__{12}$O$__6$ $\rightarrow$ 2C$__2$H$__5$OH + 2CO$__2$ H ethanoic acid + ethanol $\rightarrow$ ethyl ethanoate + water I calcium carbonate $\rightarrow$ calcium oxide + carbon dioxide J 6CO$__2$ + 6H$__2$O $\rightarrow$ C$__6$H$__{12}$O$__6$ + 6O$__2$ Use these equations to respond to the questions below. An equation may be chosen once, more than once, or not used at all. Write the letter, A to J, for the equation that shows:
May/June 2023
Which diagram indicates a chemical change?
May/June 2024
Which process results in a physical change?
May/June 2024
Which process counts as a physical change?
May/June 2024
When calcium carbonate is heated strongly, a gas is released. Which term names this change?
May/June 2024
Which process counts as a physical change?
May/June 2024
When a small piece of a Group I metal is put into a large beaker of cold water, a reaction takes place. Four statements about this reaction are given. 1 The metal melts. 2 Hydrogen is produced. 3 Steam is produced. 4 The pH of the solution increases. Which statements about this reaction describe a physical change?
May/June 2025
Which process is one that involves a chemical change?
May/June 2025
When a sample of calcium carbonate is heated strongly, substances U and V are produced. Substance U is a white solid. Substance V is a colourless gas. Which substances are U and V?
May/June 2025
Choose two processes that indicate a chemical change. Tick (✓) two boxes. boiling water burning methane dissolving salt mixing ink and water rusting of iron
May/June 2025
If green crystals of nickel(II) sulfate are heated, water is lost and a yellow solid is left behind. When water is then added to the yellow solid, the green colour comes back. Which process accounts for these changes?
Oct/Nov 2016
When heated, which substance releases carbon dioxide?
Oct/Nov 2016
Which substance releases carbon dioxide when it is heated?
Oct/Nov 2016
When some marble chips (calcium carbonate) are heated strongly, substances X and Y are produced. Substance X is a white solid that reacts with water and releases heat. Substance Y is a colourless gas. What are substances X and Y?
Oct/Nov 2017
Calcium nitrate breaks down when heated. What is the equation for the thermal decomposition of calcium nitrate?
Oct/Nov 2017
When some marble chips (calcium carbonate) are heated strongly, substances X and Y are produced. Substance X is a white solid which reacts with water and releases heat. Substance Y is a colourless gas. What are substances X and Y?
Oct/Nov 2017