topic 5: energy changes Flashcards
1
Q
what is an exothermic reaction?
A
a reaction that transfers energy to its surroundings, shown as a rise in temp
2
Q
what is an endothermic reaction?
A
a reaction in which it takes in energy from its surroundings, shown as a fall in temp
3
Q
what is an example of an exothermic reaction?
A
combustion or neutralising acids
4
Q
what is an example of an endothermic reaction?
A
reaction between sodium hydrogencarbonate and citric acid or thermal decomposition
5
Q
what causes a release or taking in of energy?
A
making and breaking chemical bonds
6
Q
what happens during a chemical reaction?
A
old bonds are broken and new bonds are formed
7
Q
bond breaking is an….
A
endothermic reaction
8
Q
bond formation is an….
A
exothermic reaction
