States Of Matter And Mixtures

Question 1

Describe particles in solid liquid and gas?

Answer 1

Solids:strong forces of attraction between particles and don’t have much energy
Fixed shape and don’t move
Can’t be compressed

Liquids:some forces of attraction has little more energy than in a solid
Can be compressed
Don’t keep definite shape
Particles free to move past each other but tend to stick together
Vibrate on the spot

Gases:no force of attraction
Don’t keep definite shape
Can be compressed
Moves around due to lots of energy

Question 2

What is the physical change of:

1. Liquid to solid
2. solid to liquid
3. liquid to gas
4. gas to solid
5. solid to gas

Answer 2

1. freezing
2. melting
3. evaporating
4. condensing
5. sublimation

Question 3

Explain how simple distillation works?

Answer 3

1. pour sample into distillation flask
2. heat distillation flask the part of solution that has low boiling point evaporates
3. vapour passes into condenser and cools and condenses
4. then flows into beaker to be collected.

Question 4

Explain how fractional distillation works?

Answer 4

1. put mixture in a flask add fractionating column and condenser over the flask.
2. heat flask
3. liquids with lowest boiling points will evaporate first.
4. liquids with higher boiling point might also start to evaporate but on the top of the column.

Question 5

Explain how filtration works?

Answer 5

Pour mixture into filter paper on the funnel liquid part runs through into the beaker leaving solid content in the filter paper

Question 6

Explain how Crystallization works?

Answer 6

1. pour solution into an evaporating dish and heat solution
2. once water starts to evaporate or see crystals start to form remove dish from the heat and leave to cool.
3. the salt should start to form crystals
4. filter crystals out of the solution and leave to dry by putting in warm oven

Question 7

What is the mobile phase and stationary phase in chromatography?

Answer 7

Mobile phase-Where the molecules can move

Stationary phase-where molecules can’t move

Question 8

Explain how paper chromatography works?

Answer 8

1. Draw line in pencil at bottom of paper put spot of mixture to be separated on the line
2. put some of the solvent in beaker and dip bottom of paper into the solvent
3. add watch glass on top of beaker to stop solvent from evaporating
4. solvent will start to move up and the chemicals in the sample will be separated
5. remove paper from beaker before solvent reaches top mark distance solvent has moved in pencil(solvent front)

Question 9

What is the formula to calculate the Rf values?

Answer 9

Rf value=distance travelled by solute/distance travelled by solvent

Question 10

Explain stages in water purification?

Answer 10

Sedimentation-iron sulfate added to water to make fine particle to settle to the bottom

Filtration-small insoluble particles removed through filtering through beds of sand

Chlorination-chlorine has is bubbled from the water to kill microbes

Question 11

Why is tap water not pure?

And how does it affect results in experiments?

Answer 11

Tap water contains dissolved salts and chlorine which makes water not pure and affects the results of experiments and causes anomalies.

Question 12

How can sea water be made potable?

Answer 12

By simple distillation first filter sea water and boil it.Water vapor is cooled and condensed to from distilled water.

Question 13

Give two advantages and one disadvantage of distilled water?

Answer 13

Advantages:
Kills microbes in the sea water
Produces pure water

Disadvantage:
Uses lots of energy so is expensive