Energy Changes In Reactions

Question 1

Law of conservation of energy?

Answer 1

States that energy can neither be created nor be destroyed

It can only be transformed from one to another

Question 2

Chemical reaction

Answer 2

When one or more substances are changed into one or more different substances

Question 3

Endothermic

Answer 3

The system gains heat as the surroundings cool down

Question 4

Exothermic

Answer 4

The system loses heat as the surroundings heat up

Question 5

Neutralization reactions are _____?

Answer 5

Neutral

Question 6

Making and breaking bonds

Breaking bonds - energy is ____ in by the system
Making bonds - energy is ____ by the system

Answer 6

Taken

Released

Question 7

System that has less energy will be more ___?

Answer 7

Stable

Question 8

How are new bonds made/formed?

Answer 8

By releasing energy

Question 9

Bond energies

Answer 9

The bond energy is the energy taken in to break bonds or energy released while making a bond.

Question 10

What is the unit of bond energies?

Answer 10

KJ/mol