reaction is where a more reactive element replaces a less reactive element in a compound.

is formed when a substance dissolves in a liquid.

are the name of salts formed from halogens, e.g. sodium chloride (NaCl).

Reactions of the halogens: including displacement practical

Chemistry

In the Chemical Analysis unit, pupils will build on their knowledge of the periodic table to explore various techniques for analysing substances and interpreting data.

In the Patterns in the Periodic Table unit, pupils learned about the arrangement of elements in the periodic table and the trends in properties of elements.

This unit explores how elements' reactions are related to electron arrangement and atomic number. It covers the properties of Groups 1, 7, and 0 and explains how these depend on outer electrons. It also predicts element reactivity and reactions based on their positions in the periodic table.

Groups of the periodic table

Physical activity and equipment requiring safe use

Which of these halogens is the least reactive?

What products are formed when chlorine gas is bubbled through a solution of lithium bromide?

Produces a squeaky pop sound when a lit splint is exposed to the gas.

Turns damp blue litmus paper red, then bleaches white.

Choose the chemical test which would indicate chlorine gas was present.

What happens when halogen atoms react to form halide salts?

A Group 1 atom transfers an outer electron to a Group 7 atom.

A Group 7 atom transfers an outer electron to a Group 1 atom.

Oppositely charged ions are formed which electrostatically attract each other.

Identically charged ions are formed which electrostatically attract each other.

What happens when a halogen and a Group 1 metal react?

bromine + potassium chloride → bromine + potassium chloride

bromine + potassium chloride → bromide + potassium chlorine

bromine + potassium chloride → chlorine + potassium bromide

bromine + potassium chloride → potassium + bromine chloride

Choose the correct word equation to show the displacement reaction between bromine and potassium chloride.

Ionic compounds formed from positive and negative ions.

Two atoms of the same type chemically bonded together.

Non metallic elements which react with metals to form halide salts.

Match the keyword to the correct statement.

Which trends occur in Group 7 elements going down the group?

What happens to the forces of attraction between atoms going down Group 7?

Going down Group 7, the molecules become more {{}} packed together and density increases.

Place the halogens in order of their density at room temperature. Place the least dense halogen first.

It becomes more difficult to gain an electron as the size of the atom increases.

It becomes easier to gain an electron as the size of the atom increases.

The distance of the outer electron from the nucleus decreases.

The distance of the outer electron from the nucleus increases.

Which statement explains why reactivity decreases down Group 7?

Content guidance

Risk assessment required - equipment

Adult supervision required

Introduction

What will you need for this lesson?

Are you ready to learn?

Equipment

Content guidance

Supervision

Worksheet