The simplest whole number ratio of atoms of each element in a compound.

Ions that are made up of more than one type of atom.

The name ending for a compound with a metal and non–metal present, for example, potassium iodide (KI).

The name ending for a compound with three or more elements present (one of which is oxygen), for example, potassium sulfate (K₂SO₄).

Determining ionic formulae

Combined science

In the Chemistry of Carbon unit, pupils will build on their understanding of chemical bonding to explore the unique properties and bonding of carbon, leading to various natural and synthetic organic compounds.

In the Atomic Structure and the Periodic Table unit, pupils learned about the model of the atom, isotopes, and the arrangement of elements in the periodic table.

Structure and bonding

Simplest whole number ratio of atoms of each element in a compound.

Shows the actual number of atoms of each element in a compound.

Name ending for a compound with a metal and singular non–metal.

Name ending for a compound with 3 or more elements, one being oxygen.

Match the following key terms to the correct definition.

The molecular formula for hydrogen peroxide is H₂O₂. What is its empirical formula? 

Which of the following are examples of ionic compounds with names ending with –ide?

Which of the following are examples of polyatomic ions?

The image shows the ionic compound lead(II) chloride. What is the empirical formula for lead(II) chloride?

The ammonium ion has the formula: NH₄⁺. Sulfate ions have the formula: SO₄²⁻. What is the formula for ammonium sulfate?

Ions form through the loss or gain of ...

When a nitrate ion forms, it gains one electron. What charge does a nitrate ion have?

True or false? Non–metal atoms gain electrons to become more stable, negatively charged ions.

The substance contains three oxygen atoms.

The ratio of hydrogen to oxygen in the formula is 3 : 4.

Which of the following statements about ammonium nitrate, NH₄NO₃, are correct?

The electrostatic force of attraction between oppositely charged ions.

The regular arrangement of atoms or ions in a 3D space.

Atom or molecule with a charge due to the gain or loss of electrons.

Match the following terms to the correct definitions.

One Mg²⁺ ion is attracted to two Cl⁻ ions.

Magnesium chloride is an ionic compound. Which of the following statements does not describe magnesium chloride?

This lesson will be removed by end of Summer Term 2025.

Determining ionic formulae

Lesson outcome

This lesson will be removed by end of Summer Term 2025.