Topic 5 - Energy Changes

Question 1

what happens if the chemicals store is more than original reactant

Answer 1

if the products of reaction store are more than original then energy takin in from surrounding during reaction.

Question 2

do chemical stores store certain amounts

Answer 2

chemicals store a certain amount of energy, different chemicals store different amounts

Question 3

what happens if the chemicals store is less than original reactant

Answer 3

if they store less then the excess energy was transferred to the surrounding during reaction

Question 4

what is an exothermic reaction and examples

Answer 4

it is when energy is transferred to the surroundings usually by heat. e.g. neutralization reactions, oxidation reactions.

Question 5

what is an endothermic reaction and examples

Answer 5

it is when a reaction takes in energy from the surrounding by decreasing temperature e.g. reactions between citric acid and sodium hydrogencarbonate

Question 6

what happens in a chemical reaction (bonds)

Answer 6

old bonds are broken down and new bonds are formed.

Question 7

how are bonds broken and formed (endo)

Answer 7

energy must be supplied to break existing bonds (endothermic process)

Question 8

how are bonds broken and formed (exo)

Answer 8

energy is released when new bonds are formed (exothermic process)