CC1/2 States of Matter, Purifying substances

Question 1

The 3 States of matter

Answer 1

Solid- Particles packed closely together, vibrate in a fixed position. Have fixed shape and volume
Liquid-Particles close together but move and flow randomly past another. Can change shape and fill a container
Gas-Particles are far apart and move randomly in all directions. Change shape and volume to fill any container

Question 2

How to determine state of substance

Answer 2

Below MP-Solid
Between MP and BP- Liquid
Above BP-Gas

Question 3

What is a mixture

Answer 3

Mixtures are made of 2 or more substances (elements or compounds) that haven’t been chemically combined. Mixtures can be separated. Their chemical properties don’t change because they have been mixed with another substance.

Question 4

More Mixtures

Answer 4

Do not have a fixed composition

Eg, Air is a mixture of gases.

Question 5

Changing State

Answer 5

When a state changes, its particles gain enough energy to overcome the weak forces of attraction between them. This happens at the melting Points and boiling points

Question 6

What is Chromotography

Answer 6

Separates solutions with a number of different solutes (solids) in the solvent (liquid).
Place a drop of the solution to be separated near the bottom of a piece of chromatography paper. Dip the very bottom of the paper into a suitable solvent. The solvent (liquid) moves up the paper and carries the solutes (solids) in the solution with it.
Different solutes (solids) move at different speeds, so they separate on the paper.

Question 7

What is Filtration?

Answer 7

Separates mixtures of insoluble (can’t dissolve) solids and liquids.
Done by pouring the mixture through filter paper:
The insoluble solid is trapped.
The liquid runs through the paper and is collected below.

Question 8

What is Crystallisation

Answer 8

Crystallisation is used to produce solid crystals from a solution. When the solution is warmed, some of the solvent evaporates leaving behind a more concentrated solution.
We can collect the solvent (liquid) by condensing it as it evaporates.

Question 9

Solutes, Solvents and solutions

Answer 9

Solute- Dissolved solid
Solvent- Dissolved Liquid
Solution- Liquid that contains a dissolved solid

Question 10

What is distillation(Simple)

Answer 10

Uses the different boiling points of liquids to separate them.
The mixture is heated until the liquid with the lower boiling point starts to boil.
The vapour released passes through a condenser, where the gas cools back into a liquid.

Question 11

Fractional Distillation

Answer 11

Fractional distillation separates a mixture containing many liquids with different boiling points.
The mixture is slowly heated until the liquid with the lowest boiling point boils and then condenses.
Then we increase temperature slowly to collect (boil then condense) the other fractions.

Question 12

Purity and Potable Water

Answer 12

Desalination- Producing pure water from sea water using simple distillation
Chemical Analysis- Using chemical reactions or sensitive machines to identify and measure substances in a sample
Chlorination-Kills micro-organisms in the water
Chemically Pure- Substance containing only 1 element or compound

Question 13

Cleaning Water Process

Answer 13

Sedimentation - removing large pieces of insoluble waste.
Filtration - removing finer pieces of insoluble waste.
Chlorination - adding chlorine to kill any microorganisms.