Topic 1 - 1.1 - Chemical Reactions Flashcards
1
Q
What is a chemical reaction?
A
When one or more substances react together to produce one or more new chemical substances.
2
Q
Define the rate of reaction
A
It is a measure of how fast the reactants are being used up and how fast the products are made.
3
Q
What are reactants and products?
A
Reactant - Substances changed by the chemical reaction
Products - Substances produced by the chemical reaction
4
Q
Name and describe 4 signs of a chemical reaction
A
- Colour change - can happen during thermal decomposition
- Effervescence - when reaction occurs inside a liquid and produces bubbles of gas
- Precipitation - when certain liquids react together to form an insoluble solid
- Energy Change - in the name
5
Q
What is an exothermic reaction?
energy change
A
Heat energy is RELEASED as reactant energy > product energy
6
Q
What is an endothermic reaction?
energy change
A
Heat energy is ABSORBED as reactant energy > product energy
