Mini Test - Earth And Space Science Flashcards
What are fossil fuels?
Substances such as oil, coal and natural gas have formed from the remains of organisms. They are used as fuel when they are burnt in order to produce heat. Eg. Coal generates electricity. Natural gas, crude oil.
Biofuels
Fuels manufactured from plant or animal materials. Eg. Biogas (methane + carbon dioxide) and ethanol (E10 is a blend of petrol and methane).
Biomass
Material produced by living organisms.
Fractional Distillation
Distillation of a mixture of substances with different boiling points. The heavier hydrocarbons have higher melting points and condense to a liquid at the lowest part of the cooling column.
Plastics
Synthetic substances,capable of being moulded. Eg. Plastics make everything including PVC pipes used for water drainage (light, rigid, doesn’t corrode).
Polymers
Plastics made up of monomers joined together in a long chain. Polyethylene (disposable plastics) and nylon.
Chemiluminescence
Light produced from chemical reactions. Eg. Glow sticks
Bioluminescence (fireflies have luciferases which cause a chemical reaction to make them glow)
What is the Hertzsprung-Russell diagram?
Absolute brightness plotted against it’s surface temperature (deduced from its colour) so that when these figures are plotted, most fall into the “main sequence”.
Apparent Magnitude
Measure of how bright a star will appear from Earth (depends on the amount of light the star emits and its distance from Earth).
Absolute Magnitude
Measure of how much light an object emits (how bright a star would appear to us if the star was 10 parsecs/310 trillion km from Earth).
Doppler Effect
Observed change in the frequency of a wave when the wave source and observer are moving in relation to each other.
How can the Electromagnetic Spectrum determine when stars are moving?
By identifying the wavelengths of the colours from the electromagnetic spectrum, astronomers can find out which elements are present in the stars.
Red Shift
A shift to a lower, redder frequency. Results from a star’s movement away from the Earth.
Blue Shift
A shift the a higher, bluer frequency. Results from a star’s movement towards the Earth.
Constellations
Groups of stars that were given a particular name because of the shape they seem to form when observed from Earth.
Nebulae
Clouds of dust that may be pulled together by gravity and heat up to form a star.
Galaxies
Very large groups of dust and gas held together by gravity.
Parallax
Apparent movement of close stars against the background of distant stars when viewed from different positions around the Earth’s orbit.
How does a supernova formate and destruct?
Stars that are over eight times larger in mass than the sun come to a very violent end. They swell to be larger that red giants and become supergiants. They then blow up, creating a supernova. The matter making up the star is hurled into space along with huge amounts of energy. Supernovas are seen every 200-300 years. They release iron and lead. The next is expected in 2022.
Hubble’s Law
The further away the galaxy is, the greater its red shift (it moves away from us faster).
Big Bang Theory
A theory which states that the universe began about 15 billion years ago with the explosive expansion of a singularity.
Planet
Large object that orbits a star. Planets do not produce their own light.
Hydrosphere
The waters. Includes water and dissolved carbon dioxide.
Atmosphere
The air. Includes oxygen, methane, carbon dioxide and ozone.
Lithosphere
The soil. Includes hummus in the soil, rocks, limestone, coal and oil.
Biota
The living things. Includes carbohydrates, lipids, proteins and organic compounds.
Biosphere
Earth’s life support system.
