Chemical Reactions


1. Chemical and Physical change


Physical Change is a change of state: (from solid to liquid to gas... or visa versa).
How do the words melting, boiling, freezing and condensing fit with these changes of state?
Try and put them in a sentence. Write this in your notes. Make a labelled diagram showing these changes.

chemicalchange.jpeg chemicalchange2.jpeg
Chemical Change is when two chemicals react together to form a new chemical.
  • Tell tale signs of a chemical reaction are... a change of colour, a change in temperature, the formation of a product, or when one of the products is completely used up.
  • You can tell what the rate of reaction is by the speed at which changes occur. An explosion is a chemical reaction which happens at a very fast rate (rate of reaction).

Use these hints to improve your answers in the following prac.

Experiment 2.1 Observing reactions

WORK IN PAIRS but each person must complete their OWN report.

Write a laboratory report which including:

Aim: To observe a variety of chemical reactions and discover the signs that a chemical reaction has taken place.
Method: Just write refer to Science for Life 8, page 23
Results: Record all your observation here. You should make these in a table with the headings of Reaction 1, Reaction 2 etc
Discussion: Talk about your results. How did they relate to the aim of the experiment. What signs were there that a chemical reaction had occurred?
Conclusion: Briefly talk about the experiment you performed and then summarise the signs that a chemical reaction has taken place.


Like to know more? Try "Science with Tom"

What are the signs that a chemical reaction has taken place?

Investigation: Rusting

Review evidence of chemical reactions

There are two alternative practical experiments for this topic. Your teacher will tell you which one you are to complete.
They are both a chance to be a real scientist!!

  1. (student designed)
  2. Rusting investigation page 25 of Science for Life 8.
    • There are three parts to this experiment
    • A: takes one week. You will begin it today and record and interpret your results the following week.
    • B: is your own design. You can try something in class, or if you need more time, try doing it at home, in two jars above the kitchen sink.
    • C: takes two days. In this cool experiment you can see how much oxygen is used in rusting by how much the water level changes.



Write up a prac report using keynote.


Rusting investigation practical write up:

Please complete the following sections for your report. You may submit it written in pages or may also record your discussion and conclusion section.

In the discussion section you should consider the following:

  • What were the results?
  • Where there any nails that didn't rust?
  • Which nail rusted the most? What were the conditions?
  • Which nail rusted the fastest? What were the conditions?
  • Which nail rusted the least? What were the conditions?
  • Were the any unexpected products produced? What did they look like. Do you think this happened in other peoples with similar reaction conditions?

In the conclusion section you should include the following information:
  • What you did (what were you testing?)
  • How you did it (what tests did you perform)
  • What the results were (sum it up, which nail rusted the least and the most)
  • Any improvements for the future (If you were to do a similar experiment again, what differences would you make to the design of the experiment.. i.e. would you use smaller nails or different water? Would you use less or more salt...)

Submit the finished report, including pictures to SIMON

2. Types of Chemical Reactions

Explain what each of the following reaction types are. Now, list the various signs which will tell you the type of reaction occurring.

Exothermic reactions

Endothermic reactions

Photochemical reactions

Do the experiment page 27 and write a small lab report.

3. Rate of reaction

Explain the difference between a slow and a fast rate of reaction. Give four examples of each type of reaction.

Complete the following practical activity:

4. Catalysts + Enzymes
Read p34-37 Catalysts and Enzymes
Pick a task:

Make a claymation which shows how enzymes work. You need to show the substrate, the enzyme and how they fit together. You should also show what happens when the enzyme denatures. You either need to narrate your film or add text to it.


Make a claymation which shows how catalysts work. You need to show the reactants and the products and how they fit together. You should also show what happens when the enzyme denatures. You either need to narrate your film or add text to it.

How to do it:

5. The Law of Conservation of Matter

MAKE a video on iMovie which explains what the law of conservation of mass is AND give an example. You may wish to film your self eating something on scales OR film some reactions, do an iStop motion movie or use some plasticine.

Glogster task: