Yeast Balloon Experiment Worksheet
What you do (Yeast is alive): 1. Pour warm (not hot) water into the bottle — an adult checks it. 2. Add the yeast and the sugar and swirl gently. 3. Stretch the balloon over the bottle’s mouth. 4. Wait 30 minutes, measure the balloon, then pour the mixture away and wash up.
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- 1.📘 What is yeast? (a) a kind of sugar (b) a tiny living fungus (c) a kind of salt (d) a kind of stone
- 2.🔮 Predict: you leave out the sugar. What happens to the balloon? (a) it grows very little (b) it grows much faster (c) it bursts at once (d) it turns yellow
- 3.🛟 After the yeast experiment, what should you do with the mixture? (a) put it in your mouth (b) pour it down the sink (c) throw it at a wall (d) keep it for a month
- 4.🧺 Which of these is not needed for the yeast balloon? (a) a small bottle (b) a balloon (c) a comb (d) warm water
- 5.🧺 Three of these are needed for the yeast balloon. Which one is NOT needed? (a) sugar (b) a battery cell (c) a small bottle (d) warm water
- 6.True or false: time is something yeast does not need. (a) False (b) True
- 7.🧺 Three of these are needed for the yeast balloon. Which one is NOT needed? (a) a balloon (b) warm water (c) a comb (d) a small bottle
- 8.🧺 Which of these is needed for the yeast balloon? (a) sugar (b) turmeric powder (c) a paper clip (d) a battery cell
- 9.🧺 Do we need a comb for the yeast balloon? (a) needed (b) not needed
- 10.⚖️ Fair test — does yeast blow up the balloon more with warm water or cold water? Which of these is kept the same? (a) size of the balloon (b) the amount of water (c) the water temperature
- 11.True or false: a mirror is needed for the yeast balloon. (a) True (b) False
- 12.⚖️ Fair test — does yeast blow up the balloon more with warm water or cold water? True or false: the amount of yeast is what we measure. (a) True (b) False
- 13.🍞 Does yeast need a magnet to make gas? (a) yeast needs it (b) yeast does not need it
- 14.🎈 What blows up the balloon in the yeast experiment? (a) air from outside (b) smoke (c) carbon dioxide gas (d) steam
- 15.🧺 Do we need a balloon for the yeast balloon? (a) not needed (b) needed
- 16.True or false: a magnet is needed for the yeast balloon. (a) False (b) True
- 17.🧺 Which of these is needed for the yeast balloon? (a) a mirror (b) dry yeast (c) turmeric powder (d) a battery cell
- 18.🔍 Which is the odd one out? (a) time (b) sugar (c) warm water (d) sunlight
- 19.True or false: warm water is needed for the yeast balloon. (a) True (b) False
- 20.True or false: warm water is something yeast needs. (a) False (b) True
- 21.⚖️ Fair test — does yeast blow up the balloon more with warm water or cold water? True or false: the amount of sugar is kept the same. (a) True (b) False
- 22.🍞 Which of these is something yeast needs? (a) sunlight (b) warm water (c) vinegar (d) salt
- 23.🔍 Which is the odd one out? (a) sugar (b) salt (c) a magnet (d) sunlight
- 24.🧺 Three of these are needed for the yeast balloon. Which one is NOT needed? (a) a balloon (b) a paper clip (c) dry yeast (d) a small bottle
- 25.🧺 Which of these is needed for the yeast balloon? (a) turmeric powder (b) a balloon (c) a paper clip (d) a magnet
- 26.⚖️ Fair test — does yeast blow up the balloon more with warm water or cold water? True or false: size of the balloon is what we measure. (a) False (b) True
- 27.🧺 Three of these are needed for the yeast balloon. Which one is NOT needed? (a) a magnet (b) a small bottle (c) a balloon (d) dry yeast
- 28.🛟 The water for the yeast should be ___. (a) warm, not hot (b) very salty (c) boiling hot (d) ice cold
- 29.🧺 Three of these are needed for the yeast balloon. Which one is NOT needed? (a) a small bottle (b) a mirror (c) sugar (d) a balloon
- 30.🍞 Does yeast need sugar to make gas? (a) yeast needs it (b) yeast does not need it
- 31.⚖️ Fair test — does yeast blow up the balloon more with warm water or cold water? Which of these is the one thing we change? (a) the amount of water (b) the water temperature (c) the amount of yeast (d) the amount of sugar
- 32.🔍 Which is the odd one out? (a) warm water (b) vinegar (c) time (d) sugar
- 33.True or false: a small bottle is not needed for the yeast balloon. (a) True (b) False
- 34.🍞 Which of these is something yeast does not need? (a) sugar (b) a magnet (c) warm water (d) time
- 35.🍞 Which of these is something yeast needs? (a) a magnet (b) sunlight (c) time (d) salt
- 36.🍞 Which of these is something yeast does not need? (a) sugar (b) warm water (c) time (d) sunlight
- 37.⚖️ Fair test — does yeast blow up the balloon more with warm water or cold water? Which of these is what we measure? (a) size of the balloon (b) the amount of sugar (c) the amount of yeast (d) the same bottles
- 38.🔮 Predict: you wait 2 hours instead of 10 minutes. What happens? (a) the balloon is smaller (b) it turns to bread (c) it shrinks to nothing (d) the balloon is bigger
- 39.🍞 Does yeast need time to make gas? (a) yeast does not need it (b) yeast needs it
- 40.⚖️ Fair test — does yeast blow up the balloon more with warm water or cold water? What do we do with “the amount of sugar”? (a) we measure it (b) we keep it the same (c) we change it
Answer key
- a tiny living fungus
- it grows very little
- pour it down the sink
- a comb
- a battery cell
- False
- a comb
- sugar
- not needed
- the amount of water
- False
- False
- yeast does not need it
- carbon dioxide gas
- needed
- False
- dry yeast
- sunlight
- True
- True
- True
- warm water
- sugar
- a paper clip
- a balloon
- True
- a magnet
- warm, not hot
- a mirror
- yeast needs it
- the water temperature
- vinegar
- False
- a magnet
- time
- sunlight
- size of the balloon
- the balloon is bigger
- yeast needs it
- we keep it the same
Free science experiments lessons, practice and worksheets at talentjr.in/science-experiments-for-kids