S2 - Geoscience (complete) Flashcards
Igneous
Rock formed as lava cools and hardens.
Sedimentary
Rock formed under water as layers of sediment settle and harden.
Metamorphic
Formed from other rocks due to heat and pressure underground.
Magma
Molten rock under the ground.
Lava
Molten rock that escapes through cracks in the Earth’s crust.
(not underground - different from magma!)
Weathering
Breakdown of rocks on the Earth’s surface.
Erosion
Gradual wearing down of rocks e.g. by water or wind.
Sediment
Fine particles of rock that settle in water.
Fossils
Plant or animal remains trapped in sediments and turned to rock.
Which type of rock can contain fossils and fossil fuels?
Sedimentary
G _ _ _ _ _ E is an igneous rock.
Granite
S _ _ _ _ _ _ _ E is a sedimentary rock.
Sandstone
M _ _ _ _ E is a metamorphic rock.
Marble
Permeable
Allows something to pass through, e.g. water.
State two properties of igneous rock
Any two of:
Contains large crystals
Hard to scratch
Water does not soak in
Does not react with acid
State two properties of sedimentary rock
Any two of:
Made of layers
Soft and easy to scratch
Water soaks in
Reacts with acid
State two properties of metamorphic rock
Any two of:
Made of small crystals or layers
Hard to scratch
Water does not soak in
Does not react with acid
Ore
Rock containing metal compounds.
Electrolysis
Using electricity to break down compounds.
What does this list show?
Reactivity series - reactive metals at the top, unreactive metals at the bottom.
How would you extract the metals in the middle from their ores?
(Iron, tin, lead)
Heating with carbon
How would you extract the metals at the top from their ores?
(Potassium, magnesium, calcium, aluminium)
Electrolysis
Corrosion
Chemical reaction of metal surfaces to form compounds.
Rusting
Corrosion of iron.
Which two things are needed for rusting?
Oxygen and water
Physical protection
Protection from corrosion by using a barrier such as paint or grease.
Sacrificial protection
Protection from corrosion by attaching a more reactive metal.
What makes iron rust faster?
Acid or salt
How does paint prevent iron from rusting?
Keeps out water and oxygen.
Galvanising
Dipping metal in molten zinc to protect it from corrosion.
Horizon
Layer within the soil.
This type of soil has large particles and drains quickly.
Sandy soil
Medium sized particles in soil are called _ _ _ _.
Silt
This type of soil has fine particles stuck together, and drains poorly.
Clay soil
This type of soil is a mixture of clay, sand and silt.
Loam
Which three nutrients do plants need to grow?
Phosphorus (P), nitrogen (N), potassium (K)
(to remember, think PiNK!)
How do plants take up nutrients from the soil?
They absorb nutrients dissolved in water through their roots.
Soluble nitrogen compounds taken in by plants
Nitrates
How do plants take in nitrogen?
In the form of nitrates through their roots.
Why is nitrogen important to plants?
Nitrogen is used to build chemicals called amino acids. Amino acids are the building blocks of protein molecules. Protein molecules are used to build new cells as the plant grows.
Decomposition
Breaking down (of dead material or chemical compounds)
Decomposers turn dead plant and animal waste back into soil nitrates.
What are decomposers?
Bacteria and fungi
Fertilisers
Compounds which help plants grow.
(contain P, N, and/or K)
Why do farmers use fertiliser?
To replace nutrients removed when crops are harvested.
Agriculture
Growing crops (food and commercial plants)
Natural fertilisers
Manure or compost. They supply plants with nutrients.
Herbicides
Chemicals which kill weeds.
Pesticides
Chemicals which kill pests.
Biological control
When a natural predator is used to kill pests (e.g. ladybirds kill Colorado beetles which harm potato plants).
