Chemistry 5070 · O Level

Elements, compounds and mixtures

62 practice questions on Elements, compounds and mixtures, with worked solutions and instant marking.

Which substance does not dissolve in water?

May/June 2015

The Contact process, the Haber process and the hydrogenation of fats each use a catalyst. Which row shows whether the catalyst used in each process is an element or a compound?

May/June 2015

Which chemical element is sodium?

May/June 2015

Which of these statements is correct?

May/June 2015

Which statement is incorrect?

May/June 2016

Which statement indicates that graphite and diamond are different forms of the element carbon?

May/June 2016

Which of the following statements about sulfur and its compounds are correct?

May/June 2017

Pick from the chlorides below to answer the questions. ammonium chloride calcium chloride carbon tetrachloride copper(II) chloride hydrogen chloride magnesium chloride zinc chloride Each chloride may be used once, used more than once, or not used at all. Which chloride is this?

May/June 2017

Which of the following statements is correct?

May/June 2018

A mineral deposit is discovered to include tiny grains consisting entirely of the element carbon. Which property will certainly be true of the carbon grains?

May/June 2019

How many elements are needed to make the compound ammonium sulfate?

May/June 2021

How many distinct elements are found in ammonium nitrate?

May/June 2022

Which of the following statements is correct?

May/June 2022

Which of the following statements is correct?

May/June 2022

Which has the largest mass of solute?

May/June 2022

Which of the following statements is correct?

May/June 2022

Which of the following statements is correct?

May/June 2022

Which row is the correct one?

May/June 2022

Which one of the statements is correct?

May/June 2023

Which of the following statements is correct?

May/June 2024

Which of the following statements is correct?

May/June 2024

What does the term tap water mean?

May/June 2024

Which of the following statements is correct?

May/June 2024

Which of the following statements is correct?

May/June 2024

Which of the following statements is correct?

May/June 2024

Pick your responses from the substances listed below when answering the questions. carbon chlorine glucose hydrated copper(II) sulfate iron magnesium sulfate methanoic acid methanol nickel silicon(IV) oxide vanadium(V) oxide Each substance may be used once, more than once, or not used at all. State which substance:

May/June 2024

Which of the following statements is correct?

May/June 2025

Which statement is the correct one?

May/June 2025

Which of the following is a compound?

Oct/Nov 2015

Which of the statements are correct?

Oct/Nov 2015

Select your answers from the gases listed below. ammonia argon carbon dioxide chlorine ethane ethene nitrogen nitrogen(II) oxide oxygen sulfur dioxide Each gas may be used once, more than once, or not used at all.

Oct/Nov 2015

Which of the following statements is correct?

Oct/Nov 2016

Which of the following statements is correct?

Oct/Nov 2017

When two elements react with one another, a compound is produced. Which statement is correct?

Oct/Nov 2017

Dry air consists of a mixture of gases, and $99\%$ of it is nitrogen and oxygen. What is the principal component of the remaining $1\%$?

Oct/Nov 2017

Which of the statements are correct?

Oct/Nov 2018

Four substances are warmed carefully. The temperatures at which melting begins and ends are noted. Which of the following statements about the substances is correct?

Oct/Nov 2018

Which of the following statements is correct?

Oct/Nov 2018

Three statements about the elements carbon, nitrogen and sulfur are given. Which of the statements are correct?

Oct/Nov 2019

Which three elements are found as diatomic molecules at room temperature?

Oct/Nov 2019

Which three elements are present as diatomic molecules at room temperature?

Oct/Nov 2019

Which option is a pure compound?

Oct/Nov 2019

Which statement is true?

Oct/Nov 2020

Which of the following statements is correct?

Oct/Nov 2020

Select answers from the compounds listed below for these questions. aluminium sulfate ammonia calcium carbonate carbon dioxide chlorofluorocarbons copper(II) sulfate hydrogen chloride potassium nitrate sodium chloride A compound may be chosen once, more than once, or not used at all.

Oct/Nov 2020

The production of sulfuric acid using the Contact process requires three different raw materials. Of these raw materials, how many are elements, how many are compounds and how many are mixtures?

Oct/Nov 2021

Which of the following statements are correct?

Oct/Nov 2021

There are two statements.

Oct/Nov 2022

Substances may be elements, compounds, or mixtures. Which row is the correct one?

Oct/Nov 2023

Which of the following statements is correct?

Oct/Nov 2023

A student gives three statements. Which of the statements are correct?

Oct/Nov 2023

Which row is the correct one?

Oct/Nov 2023

Which of the following statements is correct?

Oct/Nov 2023

Which description of a hydrated substance is correct?

Oct/Nov 2023

W represents ethene, X represents air, Y represents iodine and Z represents brass. Which row gives the correct answer?

Oct/Nov 2023

Which of the following statements is correct?

Oct/Nov 2023

X and Y are both elements, and one of them is a non-metal. 1 mole of X is mixed with 1 mole of Y, then the mixture is heated. X and Y react fully to produce substance Z. Substance Z cannot be readily separated back into X and Y. Three statements are provided. Which statements are correct?

Oct/Nov 2024

Two statements are presented. Which of the following descriptions of these statements is correct?

Oct/Nov 2024

Two compounds are each dissolved in water separately. When the solutions are then mixed together, no visible change is observed. Which two compounds are they?

Oct/Nov 2025

The principal constituent of mineral X is calcium carbonate, $\mathrm{CaCO_3}$. X also includes very small particles of silicon(IV) oxide, $\mathrm{SiO_2}$. No other substances are present in X. Which row identifies two statements that are correct about X?

Oct/Nov 2025

Which row shows the correct names of the two compounds?

Oct/Nov 2025

Which two substances are both insoluble in water?

Oct/Nov 2025