GCSE · Chemistry · AQA · Spec 8462

Group 1 alkali metals

One outer-shell electron links Group 1 together, while reactivity rises as you move down the group.

What you need to know

  • Group 1 elements are called the alkali metals and have one electron in their outer shell.
  • The first three alkali metals are studied in reactions with oxygen, chlorine and water.
  • Reactivity increases going down Group 1.
  • Use the single outer-shell electron and trends down the group to explain and predict Group 1 properties.

The big picture

The elements in Group 1 are called the alkali metals. Their characteristic properties are linked to having a single electron in the outer shell. The first three alkali metals are studied in reactions with oxygen, chlorine and water. Reactivity increases going down Group 1, so this trend can be used to predict how an element lower or higher in the group will behave.

TONIGHT'S REVISION

Group 1 alkali metals

Link one outer-shell electron to Group 1 properties, reactions and the increasing reactivity trend.

How to think about Group 1

Build the topic from the shared electron feature to reactions and predictions.

Higher or lower in Group 1?

Higher in Group 1vsLower in Group 1

The outer-shell pattern stays the same while reactivity changes down the group.

Focus

Relative reactivity

Higher in Group 1

Less reactive

Lower in Group 1

More reactive

The insight

Reactivity increases going down Group 1.

Outer-shell electrons

Higher in Group 1

One electron

Lower in Group 1

One electron

Group identity

Higher in Group 1

Alkali metal

Lower in Group 1

Alkali metal

Prediction from position

Higher in Group 1

Predict lower reactivity

Lower in Group 1

Predict higher reactivity

Three reaction contexts

These are the three reaction partners named for the first three alkali metals.

Relationship matrix

Tap any cell to reveal it. Tap a column header to read one property down every item.

Outer-shell electronsRelative reactivity
Higher positionAmong the first three alkali metals
Middle positionAmong the first three alkali metals
Lower positionAmong the first three alkali metals

Each cell hides a short answer and the reason behind it. Predict before you tap.

Group 1 essentials

Keep the vocabulary tight and connected.

Key points

1Group 1 elements are the alkali metals.
2Every Group 1 element has one outer-shell electron.
3Know the first three alkali metals in reactions with oxygen, chlorine and water.
4Reactivity increases down Group 1.
5Use the down-group trend to predict relative reactivity.

Worked example

Problem

Element B is below element A in Group 1. Which element should be predicted to be more reactive?

🧠

Memory hook

Group 1: one outer electron, three reaction partners, reactivity rises down the group.

⚠ Watch out

Reversing the trend: Group 1 becomes more reactive, not less reactive, going down the group.

Check yourself

How would you predict the relative reactivity of two Group 1 elements at different positions in the group?

Flashcards

(6)
What are the elements in Group 1 called?
The alkali metals.
How many electrons do Group 1 atoms have in their outer shell?
One electron.
Which three substances are used to study reactions of the first three alkali metals?
Oxygen, chlorine and water.
What happens to reactivity going down Group 1?
Reactivity increases.
What shared electron feature is linked to the characteristic properties of Group 1 elements?
A single electron in the outer shell.
How can you compare the reactivity of two Group 1 elements from their positions?
The element further down the group is predicted to be more reactive.

Tap any card to flip it, or use Study as deck to go through them one at a time. In the full lesson these run as a spaced-repetition deck — you rate each card Hard, Good or Easy and the tricky ones keep coming back until they stick.

Learn Group 1 alkali metals properly — interactive practice, marked questions and flashcards.

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