Science Exam Flashcards
An atom that is charged because it has an unequal number of electrons and protons
Ion
A positively charged ion that results from an atom losing electrons
Cation
A negatively charged ion formed when an atom gains electrons
Anion
A bond between a negatively charged anion and a positively charged cation, between a metal and a non metal
Ionic Bond
A bond formed when two or more atoms share electrons
Covalent Bond
Atoms prefer to have eight electrons in the valence shell
Octet rule
An ion that is charged that has two or more atoms that are bonded
Polyatomic Ion
An electron in a molecule that can easily move between atoms
Delocalised Electron
A metal loses electrons, metal atoms are kept together
Metallic Bond
A + B -> AB
Synthesis Reaction
AB->A+B
Decomposition Reaction
CxHy + O2 -> CO2 + H2O
Combustion Reaction (Formula)
A + BC -> AC + B
Single Displacement
AB + CD –> AD + CB
Double Displacement
A solid, insoluble compound formed in a precipitation reaction
Precipitate
A reaction used to produce solid products from solutions of ionic substances
Precipitation reaction
An ion that doesn’t take part in a chemical reaction
Spectator Ion
A substance containing a hydrogen that has the ability to donate a proton
Acid
A substance that has the ability to accept a hydrogen proton
Base
A base that dissolves in water
Alkali
A solution that consists of a base dissolved in water
Alkaline Solution
a substance that changes colour in the presence of an acid or a base
Indicator
When molecules react with oxygen, forming a metal oxide
Oxidation
Non-metals and oxygen produce large amounts of energy in the form of heat and light
Combustion (meaning)
A molecule that contains only carbon and hydrogen atoms
Hydrocarbon
A long chain molecule formed by the joining of many smaller repeating molecules (monomers)
Polymer
A small molecule from which polymers are made
Monomer
Long single chains of polymers
Linear Polymer
Long chains of polymers occasionally linked together like a ladder
Elastomer
A reaction in water. Water is used to break down chemical bonds.
Hydrolysis Reaction
How fast or slowly a reaction proceeds (e.g rust is a slow reaction, photosynthesis is a fast reaction)
Reaction Rate
The energy an object or particle has due to it’s motion
Kinetic Energy
Periodic change in the Earth’s climate (e.g. rising sea levels)
Climate Change
The temperature, humidity, rainfall and wind on particular days in a particular place (e.g. 20 degrees today in Luxembourg)
Weather
The weather conditions at a particular place, averaged over a long period of time, based on the collection and analysis of large data (e.g snow in the Northeast in January)
Climate
Radiant electromagnetic energy from the sun (e.g. ultraviolet light)
Solar Radiation
The influence of the Earth’s rotation on the direction of movement of air and water
Coriolis Effect
A line on a weather map that joins places that have the same air pressure
Isobar
Measure of how much salt is dissolved in water
Salinity
Continuous predictible directional movement of seawater driven by wind, water density, gravity
Ocean Currents
Determined by salinity and temperature, drives ocean currents
Density of Water
The apparent decrease in frequency (towards the red end of the spectrum) of light from galaxies that are moving away from the Earth
Red Shift
The apparent increase in frequency (towards the blue end of the spectrum) of light from galaxies that are moving towards Earth
Blue shift
The apparent change in wavelength (or frequency) when the source of the waves or the observer is moving; responsible for the red shift of distant stars
Doppler Effect
A reaction in which two lighter atomic nuclei fuse to form a heavier nucleus, releasing energy
Nuclear fusion
A change in the apparent position of a star against its background when viewed from two different positions
Stellar Parallax
A cloud of gas and dust in space
Nebula
In relation to Earth’s atmosphere: a state of stability, with upward forces balanced by downward forces
Hydrostatic Equillibrium
A star that has become large and bright with a cool surface, because it has run out of hydrogen fuel
Red giant
A glowing shell of gas formed when a star dies
Planetary Nebula
A small hot star that forms when a small star (e.g. our sun) runs out of fuel and slowly fades and cools
White dwarf
A remnant formed when a white dwarf star cools and gradually fades away
Black dwarf
The explosive death of a star
Supernova
a small highly dense star made mostly of neutrons
Neutron star
Efforts that aim to reduce or prevent greenhouse gas emission
Climate change mitigation
a region in space of infinite density where gravity is so strong that nothing, not even light, can escape from it
Black hole
The theory that the universe began as a hot, dense, single point at some time in the past, and since then has expanded and will continue to expand into the future
Big Bang Theory
A reaction that releases energy in the form of heat
Exothermic reaction
A reaction that absorbs energy in the form of heat
Endothermic reaction
A reaction in which an acid and a base combine to produce a metal, salt and water
Neutralisation
