Chemical Reactions

Question 1

What’s a chemical reaction

Answer 1

A change in which atoms are rearranged to make new substances

Question 2

Are chemical reactions easily reversible or not??

Answer 2

They are not easily reversible, at the end of the reaction, it’s very hard to get back the substances that you started with originally.

Question 3

Apart from making substances, what’s something chemical reactions also do

Answer 3

They also transfer energy to, or from their surroundings

Question 4

What do chemical reactions make

Answer 4

They make a lot of useful substances, like, medicines, such as paracetamol, fabrics, such as polyester, and building materials, such as cement.

Question 6

Are chemical reactions always useful

Answer 6

No, Some chemical reactions are not useful. Rusting may damage cars, bicycles, boats and bridges. Chemical reactions can also make food rot.

Question 7

Do all changes involve chemical reactions, and are they reversible

Answer 7

No, if you warm chocolate, it melts, but you still have chocolate, so it’s not a big chemical reaction. Changes of state, and dissolving, are reversible. This means you can get back what you started with, and these are called physical changes