MISSION 02 · CHEMISTRY DISCOVERY
Make an open fizzing volcano, then collect evidence that a gas appeared.
1 · Learn to Compare
Your new skill: Describe gas evidence without chasing a bigger eruption.
Revisit the skill you will reuse: Previous main-path mission
Match the names to your parts before you build. New parts appear when you first need them. You can point, say the name or show a grown-up.
This container holds and mixes liquids. Its mL marks help us measure volume: how much liquid we use.
Look for: Find the scale and the mL label. One millilitre is a small unit of liquid volume.
Before using it: Put it flat, look at the water level from the side and use readable markings. Ask for a measuring cup if the kit marks are unclear.
Your turn: Point to the 10 mL line without adding powder.
This spoon measures a repeatable amount of powder so our comparisons use the same amount.
Look for: Find the kit's supplied measure and its labelled amount. A level spoon is flat across the top.
Before using it: Use the approved kit measure, not a random kitchen spoon. Powder amount and spoon size must match the kit batch instructions.
Your turn: Show the difference between level and heaped using an empty spoon and a drawing.
A mixing stick moves liquid and powder together so we can compare how mixing affects a result.
Look for: Find the clean stirrer named in the materials.
Before using it: Use a clean stick for each sample, or rinse and dry between samples. Never taste it.
Your turn: Rehearse a gentle stir in an empty container without splashing.
Citric acid is our labelled acidic material. Dissolved in water it can change an indicator's colour and react with baking soda.
Look for: Find the sealed container with its correct label. Similar-looking powders are not interchangeable.
Before using it: Use only the stated amount, goggles and adult supervision. Experiment materials are not food. Keep away from eyes and mouth.
Your turn: Read the label with a grown-up before opening it.
Baking soda is our labelled mild base. With citric acid and water, the reaction releases carbon dioxide gas.
Look for: Find the container labelled baking soda, not baking powder.
Before using it: Use only the stated amount with adult supervision. Never close a fizzing mixture in a sealed container.
Your turn: Predict where bubbles can escape safely in the open experiment.
A tray catches spills, cups hold samples or form a model, and a dry workspace protects our tools.
Look for: Choose the exact container and dry surface in the mission list.
Before using it: Experiment cups stay separate from food and drinks. Keep electronics away from liquids and clean up before storing parts.
Your turn: Show where a spill would land and where electrical parts will stay dry.
A video demonstration will appear here when it is ready. You can follow the written step now.
Before we build, match these names to the parts in front of you. Beaker or measuring cup. This container holds and mixes liquids. Its mL marks help us measure volume: how much liquid we use. Find the scale and the mL label. One millilitre is a small unit of liquid volume. Put it flat, look at the water level from the side and use readable markings. Ask for a measuring cup if the kit marks are unclear. Calibrated kit measuring spoon. This spoon measures a repeatable amount of powder so our comparisons use the same amount. Find the kit's supplied measure and its labelled amount. A level spoon is flat across the top. Use the approved kit measure, not a random kitchen spoon. Powder amount and spoon size must match the kit batch instructions. Mixing stick. A mixing stick moves liquid and powder together so we can compare how mixing affects a result. Find the clean stirrer named in the materials. Use a clean stick for each sample, or rinse and dry between samples. Never taste it. Citric acid. Citric acid is our labelled acidic material. Dissolved in water it can change an indicator's colour and react with baking soda. Find the sealed container with its correct label. Similar-looking powders are not interchangeable. Use only the stated amount, goggles and adult supervision. Experiment materials are not food. Keep away from eyes and mouth. Baking soda. Baking soda is our labelled mild base. With citric acid and water, the reaction releases carbon dioxide gas. Find the container labelled baking soda, not baking powder. Use only the stated amount with adult supervision. Never close a fizzing mixture in a sealed container. Tray cup and dry workspace. A tray catches spills, cups hold samples or form a model, and a dry workspace protects our tools. Choose the exact container and dry surface in the mission list. Experiment cups stay separate from food and drinks. Keep electronics away from liquids and clean up before storing parts. Pause and point to the part that will do the main job in this mission. If it is missing or looks different, ask a grown-up before building.
WHAT YOU'LL USE
Kit list: match the named parts to your box and its component cards. Home list: gather these before starting; some may also be supplied in your kit. Reuse components between missions. Stop and ask a grown-up if an essential part or label is missing.
BEFORE YOU BUILD
Wear goggles. Keep your face back from the crater. Never close this reaction inside a bottle, tube or other rigid container.
YOUR REWARD
PREDICT BEFORE YOU BEGIN
Where will the first bubbles appear, and how will you know the reaction has slowed?
YOUR CHALLENGE
NEW POWER-UP
Describe gas evidence without chasing a bigger eruption.
You have just practised label, measure and keep two samples consistent. Now: describe gas evidence without chasing a bigger eruption.
BUILD PATH
STEP 1 OF 8
Place the volcano in the centre of the tray. Check that the crater is clean and dry.
A video demonstration will appear here when it is ready. You can follow the written step now.
Place the volcano in the centre of the tray. Check that the crater is clean and dry.
WHAT'S REALLY HAPPENING?
Citric acid and baking soda react in water and make carbon dioxide gas. The escaping bubbles are evidence of the reaction. A large, long-lasting foam is not guaranteed without a bubble-stabilising ingredient; do not add extra chemicals to force the effect.
Gas-forming reactions are used in baking, effervescent tablets and some cleaning products.
FAIR-TEST CHALLENGE
Repeat with 30 mL water while keeping both powder amounts the same. Compare the speed, height and duration. Change only the water amount.
WHEN IT DOESN'T WORK YET
WHAT YOU SEE LIKELY REASON TRY THIS FIRST Nothing happens The powders did not meet enough water, or one material is missing. Check both labels, stir the citric acid into the water, and try again with fresh dry materials. Only a few bubbles appear The crater may be wet or the powders may be old. Dry the volcano and repeat using the stated level measures. Foam escapes the tray The pour was too fast or too much material was used. Stop, clean up, and use only the stated quantities next time.
CLEAN, RESET AND STORE
Pour the used liquid down the sink with plenty of water. Rinse the volcano, tray, beaker and stick. Dry everything before returning it to the kit.
NEXT SKILL
Use a small indicator mark to detect acidity.