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Propose a hypothesis PowerPoint Presentation
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Propose a hypothesis

Propose a hypothesis

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Propose a hypothesis

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  1. Propose a hypothesis Fresh pineapple causes the jelly to remain in liquid form.

  2. 1. How much jelly powder and water would you use to prepare the jelly solution ? Why ? Follow the recommendedquantities as stated on the packet.

  3. 2 Method II : Prepare a single stock jelly solution and pour equal volume of the solution into different containers. This makes sure that the concentrations of the jelly solution in different containers are the same. (均一濃度)

  4. Identifyingvariables, 這是重要的 !

  5. Designing the set-up (= 實驗裝置)

  6. Are you sure ? Sure ! Can you ensure (保証) that ………. reliable可靠 / 可信賴 ?

  7. Collecting data : 1. How do you record and show the data ? 2. How can you ensure that the results are reliable ? Make sure that the controlled variables are the same in each set-up. Repeat the experiment a few times.

  8. Risk assessment and safety precautions : 1. What are the potential hazards in this experiment ? The hot water to dissolve jelly may hurt our body. The sharp knife to cut pineapple (especially its tough skin) may hurt our fingers.

  9. Risk assessment and safety precautions : 2. What safety precautions should be taken ? Wear a pair of thick gloves or use wet towel when handling hot water. Handle the sharp knife with extra care.

  10. Analysis and discussion : • What is the purpose of a controlled • set-up ? •  It is used to confirm (ensure) that • the presence of fresh pineapple • is the onlyfactor that • prevents the jelly from setting.

  11. Analysis and discussion : 2. What are the possible sources of errors in this experiment ? Suggest two ways for improvement.