Our Planet Rocks

Question 1

Properties + Examples of metals

Answer 1

-solids
-lustre
-ductile
-malleable
-good conductivity
e.g. gold, silver, iron, copper

Question 2

properties + examples of semi-metals

Answer 2

-metallic lustre
-properties of both metals + non-metals
-brittle
-semi-conductive
e.g. silicon, boron

Question 3

properties + examples of non-metals

Answer 3

-Solid, liquid or gas
-dull
insulation
-brittle
bad conductivity
e.g. chlorine, oxygen

Question 4

Element properties

Answer 4

-pure substance - cannot be separated
-Made up of one element
-fixed chemical composition

Question 5

compound properties

Answer 5

-pure substance- cannot be separated
-made up of two or more elements chemically bonded
fixed ratio

Question 6

mixture properties

Answer 6

-impure substance - can be easily separated
-no fixed ratio
-not chemically bonded
-can be made up of elements and/or compounds

Question 7

magnetic attraction

Answer 7

the process of separating components of mixtures by using magnets to attract magnetic materials e.g. mining

Question 8

decantation

Answer 8

separating mixtures by removing a liquid layer that is few of sediment e.g. washing rice

Question 9

sieving

Answer 9

separating smaller particles from bigger ones by passing them through a sieve - components = different sizes e.g. flour when cooking

Question 10

filtration

Answer 10

separate solids from liquids or gases using a filter medium that allows the fluid to pass through but not the solid e.d coffee filters

Question 11

evaporation/crystillasation

Answer 11

separating our homogenous mixtures where these is one or more dissolved solutes e.g salty water

Question 12

decantation

Answer 12

separating mixtures by removing a liquid layer that is few of sediment e.g. eashing rice

Question 13

signs of a chemical change

Answer 13

-change in colour
change is smell
-new solid(precipitate) forms from mixing 2 liquids
-bubble form from mixing
-change in water
light produced

Question 14

demonstrate that in a chemical change new substances are formed

Answer 14

-new substance is formed
-cannot be reversed easily
-original substance is changed

Question 15

compare physical and chemical changes

Answer 15

in a physical change the chemical composition is not affected and stays the same, generally it is a state change e.g. water to liquid or a change in shape e.g. chopping wood. In a chemical change the chemical composition of the substance is changed and cannot be reversed e.g. burning wood, cooking an egg

Question 16

What is weathering? give examples of both physical and chemical weathering

Answer 16

weathering is the breaking up of rocks into smaller pieces. In physical weathering, the chemical structure is changed e.g. animal activity or plant roots. Chemical weathering is when the chemical structure in the minerals is changed e.g oxidation or acid rain

Question 17

Erosion meaning and examples

Answer 17

Erosion is the process in which weathered rocks are carried away. Main causes of erosion: water, wind ice.

Question 18

layers of the earth

Answer 18

Geological history can be interpreted in rock layers as the bottom layers are the oldest while the top layers are the youngest. If there is an intrusive rock piercing all layers, it is the youngest as it was able to go through all layers unobstructed.