describe the difference between physical changes and chemical changes in terms of what happens to the matter..

Question

involved in each kind of change.

Answer 1

In a physical change the material changes shape or state of matter (solid, liquid, gas). It is the closeness of the particles that change.

In a chemical change the atoms re-arrange themselves into different groups and the properties of the material change.

EX:
Table salt (NaCl) can be melted. In its liquid form the ions are able to move around more. It is still table salt and can be cooled to form salt crystals again.

Table salt is formed when two elements join. One element is Na metal which is very reactive and will explode upon contact with water. The other element is chlorine gas (Cl2) which is a deadly poison. The two elements lose their old properties and take on new ones when they form NaCl. They cannot be turned back into the separate elements by cooling or heating. They can only chnge back through a chemical reaction.