9F end of topic Flashcards
Give examples of a physical change.
Melting, condensation, freezing, boiling
What’s one difference between physical change and chemical reaction?
Physical changes are often easy to reverse whereas chemical reaction are difficult to reverse.
An example of a chemical reaction?
Combustion, Neutralisation, Thermal decomposition, Oxidation
What is gas pressure caused by?
Gas pressure is caused by the force of gas particles hitting the walls of the container they are in.
What can increase gas pressure? Give examples and why.
1.) Decreasing volume of the container - Gas particles will be more packed in closely together therefore resulting in them hitting the walls of the container more.
2.) Increase the amount of particles - Same reason as above.
3.) Increase the temperature - The particles will move faster due to the temperature increasing, meaning they will hit the walls of the container with more force.
What is the test for oxygen?
It relights a glowing splint.
How do exothermic reactions happen?
In exothermic reactions, energy is created by breaking bonds between atoms. This energy is released in the form of heat or light hence why temperature increases in the surroundings of an exothermic reaction.
