Chemistry 5070 · O Level
Physical and chemical changes
13 practice questions on Physical and chemical changes, with worked solutions and instant marking.
Hydrated sodium carbonate breaks down when it is heated in a Bunsen burner flame. Which equation represents this decomposition correctly?
May/June 2016
Look at the three reactions below. $1$ reaction of ammonium chloride with calcium hydroxide $2$ ethane combusting in air $3$ the reaction of ethanoic acid with ethanol Which statement is true for all three reactions?
May/June 2017
Silicon(IV) chloride, $\text{SiCl}_4$, has a boiling point of $58^\circ\text{C}$. Which row gives the type of change when silicon(IV) chloride boils together with the reason?
May/June 2024
Which physical changes give out heat and are both exothermic?
May/June 2024
Which process counts as a chemical change?
May/June 2025
Which physical changes, in each case, are exothermic?
Oct/Nov 2015
Three different solution-and-solid mixtures are prepared, as shown in the table. The mixtures are then heated. In which mixtures is gas produced?
Oct/Nov 2018
Octane, $\text{C}_8\text{H}_{18}$, belongs to the hydrocarbon family. When octane is combined with an excess of oxygen, nothing happens unless energy is added. Once energy is added, either as heat or an electric spark, the change occurs rapidly. The products formed in this change include carbon dioxide. Which detail in this description indicates that the change is a chemical change?
Oct/Nov 2023
Substances can undergo physical changes or chemical changes. Which process describes a chemical change?
Oct/Nov 2023
On heating, crystals of copper(II) sulfate, $\text{CuSO}_4\cdot5\text{H}_2\text{O}$, undergo the reaction shown below. $\text{CuSO}_4\cdot5\text{H}_2\text{O}(s) \rightarrow \text{CuSO}_4(s) + 5\text{H}_2\text{O}(g)$ If .....1..... copper(II) sulfate, which has a .....2..... colour, is heated, it produces .....3..... copper(II) sulfate, which has a .....4..... colour. Which words should be used to fill gaps 1, 2, 3 and 4?
Oct/Nov 2024
Which statement concerning a physical change is correct?
Oct/Nov 2024
Which statement concerning reactions is correct?
Oct/Nov 2025
Two reactions are given. Reaction 1: Copper is put into concentrated nitric acid. Nitrogen dioxide is formed. Reaction 2: Concentrated sulfuric acid is put into sugar. The reaction that happens cannot be reversed. Which row is correct?
Oct/Nov 2025