C6 energy changes

Question 1

Exothermic

Answer 1

When a reaction releases heat energy. The temperature increases (returns to room after the reaction is complete) and the delta H is negative. It creates bonds–> gives out energy.

Question 2

Endothermic

Answer 2

When a reaction takes in heat energy (absorbed) The temperature decreases (returns to room after reaction is complete) and the delta H is positive. Bonds are broken–> energy taken in.

Question 3

Specific heat capacity

Answer 3

The amount of energy needed to raise the temp of 1 gram of water by 1 degree Celsius

Question 4

Bond energy

Answer 4

The energy required to break a particular covalent bond (measured in J or kJ/mol)

Question 5

Delta H

Answer 5

The difference in bond energies between the reactant molecules and the product molecules in a chemical reaction

Question 6

Fuel

Answer 6

Any kind of substance which releases energy on burning

Question 7

Combustion

Answer 7

Burning