Fundamental Ideas In Chemistry Flashcards
When would you use filtration to separate a mixture ?
When you have a mixture containing at least one insoluble component that you with to separate out
What is a mixture
A substance made by mixing other substances together
When would you use distillation to separate a mixture
Distillation would be used to separate liquids with different boiling points
When would you use crystallisation to separate a mixture
When you want to separate saturated solutions by leaving them to form crystals
Describe an experiment to show that black ink contains 2 dyes
Chromatography
What is meant be an Rf value. How do you calculate it.
The Rf value is a measurement of how far the compound you are studying has moved along
Distance moved by the compound / distance moved by the solvent
Describe the arrangement of particles in a solid
Close together, regular pattern
Describe the arrangement of particles in a liquid
Close together, random arrangement
Describe the arrangement of particles in a gas
Far apart, random arrangement
What happens to the particles in solid when they are heated
They vibrate when heated and take up more room
What happens to the particles of a solid at melting point
Move around, which produces heat which causes it to melt
What happens to the particles in a liquid when heated
Move around each other and take up more room
What happens the particles of a liquid at boiling point
The energy increases forcing it to evaporate
What is sublimation
A solid going directly to a gas
What is diffusion
Diffusion is the movement of any substance from a higher concentration to a lower concentration of that substance
