Work your way through the powerpoint looking at changing states. When you get to slide 8, where it asks 'what are the states of the things below?', answer the questions in your workbook before revealing the answer with a click! See how many you got correct.
Then watch the video below on reversible and irreversible changes. Remember from this video that:
A reversible change is something which can turn back into the state it was before, exactly how it was before.
e.g. Water --> - heat (freezing) ---> Ice
Ice ---> +heat (melting) ---> water
An irreversible change is something which cannot turn back into the state it was before.
e.g. Egg ---> + heat ---> cooked egg (fried/scrambled)
Cooked egg ---> - heat ---> cold cooked egg (cannot go back to original state)
Download the document titled 'changing state'. You could either print this off at home or if not just copy the statements into your work book.
For example: Egg (item) After it was heated, the egg became hard-boiled. Irreversible change