Studied by 0 peopleWhat are the properties of solid state?
Strong forces of attraction, fixed position
What are the properties of liquid state?
Weak forces of attraction, free to move, definite volume
What are the properties of gaseous state?
Very weak forces of attraction, constantly moving
What is the definition of a pure substance?
Contains only one type of compound or element
What is the definition of mixture?
Two different compounds
What is a physical test?
Testing the physical properties
What is a chemical test?
Reacting the substance with another chemical
How does impure substances affect the melting and boiling point?
It ranges its temperature
In samples, how do impure substances change the melting and boiling points?
They lower the melting point and increase the boiling point
What is the definition of formulations?
Mixtures that have been prepared using a specific formula
What is the purpose of simple distillation?
Used to separate a liquid from a mixture, but we still want to keep the liquid
Describe the process of simple distillation
The solution is placed in a flask and heated so that the liquid evaporates into vapour. The vapour passes through a condenser and condenses back into liquid which is collected
Why can you not use simple distillation for mixtures that contain multiple different liquids?
The liquids may have the same boiling points so would evaporate together
When would fractional distillation be used rather than simple distillation?
When the mixture contains multiple liquids with similar boiling points
How does fractional distillation work?
A solution is gently heated, the liquid with the lowest boiling point evaporates and passes through the fractioning column. It goes through the condenser and condenses back into liquid. This process then repeats
What is the fractioning column filled with and why is it used?
Glass rods - provide a large surface area which cause gases to condense back to liquids
What are the 6 methods through which mixtures can be separated?
Filtration, chromatography, crystallisation, evaporation, simple distillation and fractional distillation
What is filtration used for?
To separate insoluble solids from liquids
What is the filtrate in filtration?
Any liquid or dissolved substance that passes through the filter paper
What is the residue in filtration?
Any insoluble solids caught by the filter paper
What is evaporation used for?
Separate a dissolved solid from a liquid
What is chromatography used for?
To separate mixtures and give information to help identify substances
What is the mobile phase in chromatography?
The solvent
What is the stationary phase in chromatography?
The paper
How many spots do pure substances produce in paper chromatography?
One spot
How many spots do impure substances produce in paper chromatography?
More than one
What is an Rf value?
The ratio between the distance travelled by the dissolved substance and the distance travelled by the solvent
How to calculate Rf value?
Distance travelled by substance / distance travelled by solvent
What does potable mean?
Safe to drink
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