C2.5: Describe chemical changes in matter as changes that result in the…

Kitchen Chemistry for Families Grades K–5

Four famous kitchen experiments, done properly: a homemade lava lamp, oobleck, a baking soda volcano and invisible ink. Each one starts with a real question, works with things from your cupboard, and leaves your child able to explain what happened.

• Why do the blobs in a lava lamp go up and down? 45 min

  Kids layer oil and water in a glass, add food colouring and a piece of fizzy tablet, and watch coloured blobs rise and sink. Then they explain it with floating, sinking and gas bubbles, and test whether warm water changes the show.

• Is oobleck a solid or a liquid? 45 min

  Kids mix cornstarch and water into oobleck, then poke, squeeze, slap and drip it to find out when it acts like a solid and when it acts like a liquid. They finish able to explain why speed and force change the way it behaves.

• What makes a volcano erupt? 45 min

  Kids test baking soda and vinegar to find out where the fizz comes from, build the classic kitchen volcano, then open bottles of sparkling water to see what really drives an eruption: gas trapped under pressure. They finish able to explain how the model is like a real volcano, and how it isn't.

• How do spies write secret messages? 45–60 min

  Kids write invisible messages in baking soda, then reveal them by painting on grape juice or turmeric water, which change colour where the baking soda is. They finish able to explain that acids and bases make some colours change, and why a plain-water message stays hidden.

Kitchen Chemistry Grades 7–8

Fizzing, curdling and colour changes with things from the grocery store. Students gather evidence of new substances, weigh a reaction in a sealed bottle, and turn red cabbage into an acid detector.

• Is it a new substance? 50–60 min

  Teams run six quick kitchen changes, from dissolving sugar to curdling milk, and record properties before and after. They sort each change as physical or chemical using evidence, and find out why a single clue like bubbles or a colour change isn't proof on its own.

• Where does the mass go? 50–60 min

  Teams weigh baking soda and vinegar reacting in an open cup, then in a capped pop bottle. The open cup gets lighter and the capped bottle doesn't, until they open it. Students use atoms to explain why mass is never lost in a reaction, only let out.

• Can red cabbage tell acid from base? 50–60 min

  Students add purple cabbage juice to safe household liquids and watch it turn pink, purple, blue or green. They build a colour scale, sort the liquids into acids and bases, identify two mystery liquids, and watch an acid and a base cancel each other out.

Printable practice for C2.5

These pages practise a closely related idea; the match to C2.5 is partial.

• Kitchen Chemistry workbook included with the unit

  3 practice pages, 3 readings, 2 English-support pages, 1 word wall, 1 unit review, 1 unit test, with answer keys.

Need just this outcome? Build a custom pack from these pages, with its answer key, in about a minute. Custom packs come with All-access and school licences.