Which of the following occurs when substances undergo chemical changes? 1. Old atoms are destroyed and new atoms are formed
2. Bonds between atoms are broken and new bonds are formed.
3. Atoms change in size and shape to form new substances.
4. Atomes change from one element into another element.

Option 3 - Atoms change in size and shape to form new substances.

Explanation:

In a chemical change, atoms rearrange to form new substances. When a substance undergoes a chemical change, it results in different physical properties as well. Umm...two examples of a chemical change can be burning and rusting.

while cooking a piece of 1/2 pound beef steak, a cast iron pan (2.4kg in weight) was heated 260 celsius.

you did not give any options thus this is the best answer i can give to you with this little information you have given

> they are both natural and not man made

> they can be tracked and predicted by the right tools

-love shrooms