In the lab 🧪
Six amazing experiments using everyday items, a kitchen corner, an adult, and plenty of curiosity!
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🌋The erupting volcano⏱ 15 min · ⭐ EasyColorful foam spills over like real lava!
What you need
- A small plastic bottle and a large tray
- 2 tablespoons of baking soda
- White vinegar
- A drop of dish soap and red or orange food coloring
How to do it
- Place the bottle in the tray and shape sand or modeling clay around it to make a mountain.
- Pour the baking soda, dish soap, and food coloring into the bottle.
- Pour in the vinegar all at once, then step back and watch!
Why does it work? Vinegar (an acid) reacts with baking soda (a base) and makes carbon dioxide gas. The gas expands the dish-soap foam until it erupts.
🌈Rainbow milk⏱ 10 min · ⭐ EasyColors dancing all by themselves in a plate.
What you need
- A shallow dish and whole milk
- Food coloring in several colors
- Dish soap
- A cotton swab
How to do it
- Pour the milk into the dish and let it settle.
- Add a few drops of each color, without mixing.
- Dip the cotton swab in dish soap, then touch the center of the milk. The colors swirl away!
Why does it work? Dish soap interacts with the fat in the milk and moves its surface. The food coloring follows along. Use whole milk for a more dramatic effect.
🫧The lava lamp⏱ 15 min · ⭐⭐ MoyenGiant bubbles rise and fall like in a movie.
What you need
- A clear bottle
- Vegetable oil and water
- Food coloring
- An effervescent tablet and a flashlight
How to do it
- Fill the bottle three-quarters full with oil.
- Add colored water, stopping 2 cm from the top, and wait for the liquids to separate.
- Break a tablet into pieces, drop them into the bottle, then shine a light underneath.
Why does it work? Oil and water do not mix: oil is lighter, so it floats. The tablet makes gas bubbles that lift drops of colored water and then release them. Do not put the cap on the bottle.
🎈The self-inflating balloon⏱ 10 min · ⭐ EasyNo blowing, and yet the balloon grows!
What you need
- A small plastic bottle
- White vinegar et du bicarbonate de soude
- A balloon and a funnel
How to do it
- Pour 3 or 4 cm of vinegar into the bottle.
- Use the funnel to put 2 teaspoons of baking soda into the balloon.
- Fit the balloon over the bottle neck without pouring anything in. Then lift it so the powder falls in. Watch it inflate!
Why does it work? The mixture makes carbon dioxide. Gas needs space: it fills the bottle and then rises into the balloon.
🥚The bouncing egg⏱ 5 min + 2 jours d'attente · ⭐⭐ MoyenAn egg with no shell: clear and squishy.
What you need
- A whole raw egg
- A large glass
- White vinegar
How to do it
- Place the egg in the glass and cover it completely with vinegar.
- Watch the bubbles appear on the shell. Leave it for 24 to 48 hours.
- Gently rinse it under water. It is soft and see-through: shine a light to see the yolk inside. It bounces a little, but only from a very low height!
Why does it work? The shell is made of calcium carbonate, which vinegar dissolves while making bubbles. Only the thin membrane remains. Wash your hands well: the egg is raw.
🍇The dancing raisins⏱ 5 min · ⭐ EasyRaisins that rise and fall all by themselves.
What you need
- A large glass transparent
- Fizzy sparkling water
- A few raisins
How to do it
- Fill the glass with sparkling water.
- Add 5 or 6 raisins.
- Watch: they sink, bubbles attach, they rise, then sink again. The show lasts several minutes.
Why does it work? Gas bubbles stick to the raisins and make them lighter, so they float. At the top, the bubbles pop and the raisins sink again.
🌈Traveling colors⏱ 15 min · ⭐ EasyA marker reveals hidden colors in the paper.
What you need
- A white coffee filter
- A dark washable, water-based marker
- A glass with a little water
- A pencil and a clothespin
How to do it
- Cut a strip from the coffee filter and draw a large marker dot near the bottom.
- Clip the strip to the pencil and rest the pencil across the glass.
- Dip only the bottom of the paper in water, keeping the dot above the water.
- Watch the water climb and the colors separate.
Why does it work? Water climbs through tiny spaces in the paper and carries the ink with it. Some colors travel faster than others. This is called chromatography.
🌶️The pepper that runs away⏱ 5 min · ⭐ EasyA little soap sends the pepper racing to the edges.
What you need
- A shallow plate
- Water
- Ground pepper
- Dish soap and a cotton swab
How to do it
- Pour a little water into the plate and sprinkle pepper on the surface.
- Put a drop of dish soap on the tip of the cotton swab.
- Gently touch the center of the water and watch the pepper move away.
- Now touch the water without soap. What happens?
Why does it work? Water forms a thin skin at its surface. Soap weakens that skin, making the water move and carrying the pepper toward the edges.
🌉The strong paper bridge⏱ 15 min · ⭐⭐ MediumA folded sheet can hold more coins than a flat one.
What you need
- Two identical cups
- Two sheets of paper the same size
- Coins or small blocks
How to do it
- Place the cups a few inches apart.
- Lay one sheet flat between the cups and add coins one at a time.
- Count how many it holds before bending.
- Fold the second sheet into an accordion, place it like a bridge, and try again.
Why does it work? Folds make paper stiffer and spread out the weight. Engineers use similar shapes to build strong bridges.