(what's the) Matter and materials

Question 1

what is matter?

Answer 1

anything that takes up space and has a mass

Question 2

what is an element?

Answer 2

a pure substance that cannot be split into simpler substances

Question 3

what are atoms?

Answer 3

the smallest part of a chemical element

Question 4

what is the periodic table of elements?

Answer 4

a list of elements according to their atomic number

Question 5

what is made up of matter?

Answer 5

everything we can see and touch including air

Question 6

what is matter made up of?

Answer 6

atoms

Question 7

what are elements?

Answer 7

made up of atoms of the same kind

listed on periodic table of elements

divided into metals, non metals, semi metals

periods and groups

Question 8

what are sub atomic particles?

Answer 8

atoms are made up of samller particles called:

1. protons
2. electrons
3. nuetrons

Question 9

draw diagram of an atom:

Answer 9

Question 10

what is the central region of an atom?

Answer 10

nucleus

Question 11

why are atoms neutral?

Answer 11

because number of protons=nuetrons

Question 12

what are the properties of a pure substance?

Answer 12

phase

conductivity

solubility

density

magnetism

melting point

boiling point

Question 13

what are molecules?

Answer 13

two or more atoms chemicals bonded to form a unit

Question 14

what are compounds?

Answer 14

different elements reacted chemically to form molecules of compounds

Question 15

what is the ratio of atoms in compounds?

Answer 15

atoms in a compound are combined in a fixed ratio

water = 2 : 1 (two hydrogen atoms and one oxygen atom)

Question 16

how are the atoms in molecules held together?

Answer 16

by a chemical bond

Question 17

what is a chemical bond?

Answer 17

strong forces of attraction that holds atoms together

Question 18

how are compounds formed?

Answer 18

by means of chemical reactions

Question 19

what does decomposing a compound mean?

Answer 19

when compound is broken down into its composite elements

Question 20

how can substances be decomposed?

Answer 20

*triangle*

heating. example: mecury oxide ———————> mercury + oxygen

electrolysis, decomposing using electrical energy

Question 21

what is a mixture?

Answer 21

a combination of two or more substances that have not yet reacted chemically and can be seperated by physical processes

Question 22

name the methods of seperating mixtures

Answer 22

hand sorting

magnetic seperation

filtration

seperation funnel (remember:(seperation fun))

distillation:

• evaporation
• fractional distillation

chromatography

Question 23

name the conditions for substances to be hand sorted

Answer 23

both substances must be solids and big enough to pick up with your hands

example: peanuts and raisens

Question 24

name the conditions for substances to be magneticly seperated

Answer 24

one substance must be magnetic and the other non magnetic

example: iron filings and sulphur powder

Question 25

name the conditions for substances to be filtrated

Answer 25

one substance must be a liquid and the other a solid which is insoluble in a liquid ## Footnote ***_example: sand in water_***

Question 26

name the conditions for substances to be seperated with a funnel (or funnily seperated)

Answer 26

substances with different desities can be seperated with a funnel

Question 27

name the conditions for substances to be seperated by (distillation) evaporated

Answer 27

a slid dissolved in a liquid ## Footnote ***_example: sugar and water_***

Question 28

name the conditions for substances to be seperated by fractional distillation

Answer 28

substances (liquids) with different boiling points ## Footnote ***_example: alcohol and water_***

Question 29

what is chromatography?

Answer 29

rate at which different dissolved substances move in a solute ## Footnote ***_example: filter paper and ink_***

Question 30

what are the states of matter?

Answer 30

![]() solids, liquids, gases

Question 31

name the properties of a solid

Answer 31

* particles packed closeley together * small spaces between particles * strong forces of attraction between particles * particles do not move freely ( vibrate ) * fixed shape

Question 32

name the properties of a liquid

Answer 32

* particles are close together but looseley packed * particles can move around quickly * weaker forces of attraction between particles than in a solid * small spaces between particles

Question 33

name the properties of a gas

Answer 33

* particles are wideley spread no fixed shape * moves fast and freely * weak forces of attraction between particles * large spaces between particles

Question 34

what is diffusion?

Answer 34

the movement of particles in a liquid or gas from an area of high concentration from an area of low concentration until evenly distributed

Question 35

how is diffusion a result of kinetic energy?

Answer 35

gas particles move faster than liquid particles therefore there is more kinetic energy diffusion is faster in a gas than a liquid

Question 36

what is change of state?

Answer 36

when a matter changes into another state or form heating or cooling can cause change of state

Question 37

what happens when matter is heated?

Answer 37

particles gain more kinetic energy * particles vibrate more * particles knock against each other, particles start to expand * eventually particles begin to break away from their position and can move past each other * at low temperature parts of a liquid move slowly * liquid heated, more kinetic energy, expands = a gas * liquid is therefore evaporating

Question 38

what happens when matter is cooled?

Answer 38

when particles cool ----\> less kinetic energy particles move closer together

Question 39

what is density?

Answer 39

amount of mass per unit for that material density = _{mass(g) ——————— volume}

Question 40

what can density tell us?

Answer 40

how closeley packed the particles are in a material

Question 41

what has a higher density than the same material in liquid or gas form?

Answer 41

solids 1. exception: water * ice cubes float on water * water expands when frozen

Question 42

is solid water less dense than liquid water at the same temperature?

Answer 42

yes

Question 43

what does density of materials depend on?

Answer 43

particles state of matter: ***_example: mass of particles_*** ***_size of spaces between particles_*** ***_kinds of particles_***

Question 44

would a material with a low density float on a liquid with a high density?

Answer 44

yes

Question 45

what is expansion?

Answer 45

* to grow in size or become larger * happens when materials gain energy * partcles move faster * forces between particles weakens * particles move further apart

Question 46

what is contraction?

Answer 46

* to become smaller or shrink * materials lose energy (cool down) * particles move slower * forces between particles become sronger * particles move closer together

Question 47

explain how can expansion and contraction be dangorous

Answer 47

in cold countries pipes can freeze, water in pipes expand when frozen, pipes can therefore burst

Question 48

what is pressure?

Answer 48

* gas particles in a container move around very quickly * they bump into each other and collide with container * when gas particles hit wall of container = apply force * this is called gas pressure * the more particles collide with the walls, the greater the pressure