states of matter and mixtures

Question 1

what are some structures of solids

Answer 1

-fixed positions
-regular lattice arrangement
-definite shape

Question 2

what are some properties of liquids

Answer 2

-free to move but still touch each other
dont have definite shape

Question 3

what are some properties of gases

Answer 3

dont keep a definite shape
-has the most energy

Question 4

what is solid to liquid

Answer 4

melting

Question 5

what is liquid to solid

Answer 5

freezing

Question 6

what is liquid to gas

Answer 6

evaporating

Question 7

what is gas to liquid

Answer 7

condensing

Question 8

what is solid to gas

Answer 8

subliming

Question 9

what does it mean if a substance pure

Answer 9

it is made up of only a single element or compound

Question 10

how do you test how pure a substance is

Answer 10

a pure substance has a fixed and specific melting and boiling point. by heating the substance and recording the melting point, you can compare it to the expected value. if it is a mixture, it will give a range of melting points

Question 11

what are the two types of distillation

Answer 11

simple and fractional

Question 12

what is simple distillation used for

Answer 12

separation of a liquid from a solution

Question 13

how is the method of simple distillation carried out?

Answer 13

heat the mixture until the liquid is evaporated. then collect that liquid

Question 14

what is fractional distillation used for?

Answer 14

separation of a mixture of liquids.

Question 15

how is the method of fractional distillation carried out

Answer 15

place the mixture in a fractional column. as you heat this, the different liquids will have different boiling points so they will evaporate at different temperatures

Question 16

what is filtration used for

Answer 16

to separate an insoluble solid from a liquid

Question 17

what is crystalisation used for

Answer 17

separates a soluble solid from a solution

Question 18

what is the mobile phase in chromotography

Answer 18

this is where the molecules can move. this is a liquid or gas

Question 19

what is the stationary phase in chromotography

Answer 19

this is where the molecules cant move. this is a solid or a thick liquid

Question 20

how do you calculate the rf value in chromotography

Answer 20

distance travelled by solute/distance travelled by solvent

Question 21

what is potable water

Answer 21

water that is safe to drink

Question 22

what are the three methods to purify water

Answer 22

-filtration
-sedimentation
-chlorination

Question 23

what is the filtration method in the purification of water

Answer 23

a wire mesh screens out large solids

Question 24

what is the sedimentation method in the purification of water

Answer 24

iron or aluminium sulfate is added to the water. this makes small particles stick together and fall to the bottom

Question 25

what is the chlorination method in the purification of water

Answer 25

chlorine gas is bubbled through to kill harmful bacteria