1. a change in temperature is always an indicator of a chemical reaction. true or false? 2. a color change is an indicator of a chemical reaction. true or false? 3. a change in size is an indicator of a chemical reaction. true or false? 4. the release of gas is an indicator of a chemical reaction. true or false? 5. the formation of a precipitate is an indicator of a chemical reaction. true or false? 6. a change in state is an indicator of a chemical reaction. true or false?

1)true

2) false

3) false

4) True

5) True

6)false

Explanation:

The release of a gas shows a chemical interaction between species. The gas is a product of the reaction. Also, when a precipitate is formed, a chemical reaction have taken place because the precipitate is the insoluble product of the reaction. Change in temperature shows that chemical interaction between the species is either exothermic or endothermic hence it shows that a chemical reaction has taken place.

- aluminum and copper chloride.

- the chloride ion to separate the aluminum from the oxygen so that the aluminum can react with the copper ions (and the water molecules).