Materials From The Earth Flashcards
How is sedimentary rock formed
Over the years layers of sediment build up at the bottom of lakes or seas
Over millions of years the immense pressure and weight squeezes out the water causing the rock to be formed
Fluids flowing trough pores deposit a natural mineral cement
What are types of sedimentary rocks
Limestone and chalk
They contain fossils
They can be eroded easily
How is metamorphic rock made
Formed by immense heat and pressure of sedimentary or igneous rocks over time
The mineral structure and texture may have changed but the chemical composition is still the same as the original rock
As long as the rocks don’t melt they are classed as metamorphic
What are the types of metamorphic rock
Marble
It has a more even texture and is much harder than the original chalk or limestone
How is igneous rock formed
When molten magma punches up into the earths crust before cooling and solidifying
Extrusive igneous cool quickly above the ground forming small crystals
Intrusive igneous cool slowly unter the ground and form big crystals
What are the types of extrusive igneous
Basalt and rhyolite
What are they types of intrusive igneous
Granite and gabbro
What are the uses of limestone
It is a grey white colour and is quarried underground
It is good for buildings and statues because it can be easily shaped
It can be crushed up into road chippings and used for road surfaces
When heated with powdered clay it can make cement
This can be mixed with sand water and gravel to make cement
When heated with sand and sodium carbonate it is used to make glass
What are the bad points about quarrying limestone
It makes huge ugly holes which destroy the landscape
It makes loud noises and dust
Destroys the habitats of animals and birds
It must be transported away which creates more noise and pollution
Waste materials produce ugly tips
What’s the good thing about quarrying limestone
Limestone provides things that people want like houses and roles
Limestone can be used to neutralise acidic products
It is used in power stations to neutralise sulfur dioxide
The quarry provides Jobs and money for the local economy
What is the equation for the thermal decomposition of calcium carbonate
Calcium carbonate -> calcium oxide and carbon dioxide
CaCO3 -> CaO + CO2
What does the speed of the thermal decomposition depend on
The stability of the metal carbonate
Less stable carbonates will decompose faster
How is calcium hydroxide made and what are its uses
Calcium oxide + water -> calcium hydroxide
It is an alkali which can be used to neutralise acidic soil
It dissolves in water to product lime water
If you react 6g of magnesium fully with 4g of oxygen how much magnesium oxide would you get
10g of magnesium oxide
What is a precipitation reaction
When two solutions react and an insoluble solid is formed it is called the precipitate
