How can you tell they’ve got it: Acids, Alkalis & pH?

If they’ve got it, you’ll see things like: States that acids have pH below 7, alkalis have pH above 7, and neutral is pH 7; Explains what hydrogen ions (H⁺) have to do with acidity; Names common indicators (litmus, universal indicator) and describes colour changes; Identifies everyday acids (vinegar, lemon juice) and alkalis (bleach, bicarbonate of soda). Or just try it together: If your child used a piece of universal indicator paper to test lemon juice and baking soda solution, could they predict what colour each would turn and explain what that tells you about each substance?

Science Matter & Materials Ages 12–13

Acids, Alkalis & pH

Your child can test how acidic something is with indicator paper. Lemon juice turns it red, below 7. Baking soda turns it blue, above 7. Seven is neutral.

In curriculum terms

Define acids and alkalis in terms of hydrogen ion concentration, describe the pH scale (0–14), and explain how indicators are used to identify and measure acidity or alkalinity

Ages are typical, not deadlines — follow your child’s pace. How to help at home →

How to tell they’ve got it

Tick these off as you see them — no test required.

States that acids have pH below 7, alkalis have pH above 7, and neutral is pH 7
Explains what hydrogen ions (H⁺) have to do with acidity
Names common indicators (litmus, universal indicator) and describes colour changes
Identifies everyday acids (vinegar, lemon juice) and alkalis (bleach, bicarbonate of soda)

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Try this together

If your child used a piece of universal indicator paper to test lemon juice and baking soda solution, could they predict what colour each would turn and explain what that tells you about each substance?

Where this sits on the map

Stuck here? Check the skills it builds on first. Confident? Here’s what it unlocks.

Builds on

Atoms, Elements & Compoundsages 11–12Acids are defined in terms of hydrogen ions — the concept of ions and atomic structure is needed

Coral Bleaching & Acidificationages 12–13KS3 acids/pH and carbonic acid chemistry underpins the ocean acidification mechanism that dissolves coral skeletons

Acids, Alkalis & pHthis skill · ages 12–13

Unlocks

Acid Reactions & Saltsages 12–13The reactions of acids with metals and bases require first understanding what acids and alkalis are

solid = must come firstdashed = helps

Curriculum alignment

Where this fits in the official school curriculum — our best automated guess, not yet checked by a person.

This skill sits beyond Year 6 in the Australian Curriculum, so no F–6 code is matched. It also sits beyond the NSW K–6 syllabuses. It also sits beyond Level 6 in the Victorian Curriculum.

Nearby on the map

Acid Reactions & Saltsages 12–13 Earth's Atmosphere & CO2ages 12–14 Finite Resources & Recyclingages 12–14 Reactions That Release or Absorb Heatages 12–13

All Matter & Materials skills →