Chemistry Revision Flashcards
Reactants
substances present at the beginning of a chemical reaction
Products
substances created by the chemical reaction
Valency
the number of bonds an element has
Democritus
400 BC
claimed everything was made up of invisible atoms that were tiny spheres
John Dalton
1803 AD
agreed with Democritus that atoms were tiny spheres and could not be divided into anything smaller, suggested different elements were different sizes
JJ Thompson
1904 AD
claimed atoms were made up of positive energy with negative energy scattered throughout like raisins in a plum pudding
Ernest Rutherford
1911 AD
claimed that there was a positive charge in the nucleus and that electrons were on the outside, not scattered randomly, used his model in the gold foil experiment
Bohr
1912
claimed positive charge was concentrated in the nucleus, claimed electrons were in fixed positions on energy shells
James Chadwick
1932
was developed after the neutron was discovered
Atomic Number
number of protons, same as number of protons, can be taken away from the atomic mass to get the number of neutrons
Relative Atomic Mass
average mass of all isotopes that exist, can have the atomic number taken away to get the number of neutrons
Abundance
amount
Relative Atomic Mass
% of isotope 1 * mass/100 + % of isotope 2 * mass/100
Oxidation
the process by which something gains oxygen
Oxidised
something that has gained oxygen through oxidation
Reduction
removal of oxygen, antonym of oxidation
Variable
something in a reaction that can be changed
Independent Variable
the variable you change
Dependent Variable
the variable you measure
Control Variable
the variable that stays the same
Quantitative Data
data that includes numbers, e.g. temperature, volume or mass
Qualitative Data
data you can see, but not measure, such as whether or not there are bubbles
Chromatography
separates substances made up of a mixture of differently coloured components
Rf Value
distance moved by colour/distance moved by water
Non-Metals
have negative ions and gain electrons
Metals
have positive ions and lose electrons
Base
a substance that neutralises an acid and is insoluble
Alkali
a soluble substance that neutralises an acid
Acid Concentration
how many particles of acid in one decimetre cubed, measured in mol/dm^3
Acid Strength
how ionised the acid is
Metabolism
the sum of all the reactions in the body
Mean Rate of Reaction
quantity of reactant used/time or quantity of product formed/time
Collision Theory
explains why rate of reaction changes, states that particles must collide before a reaction takes place and if there is a collision, it might take place, but not all collisions lead to reactions because they need energy in order to react, and reactants must have the activation energy in order to react
Activation Energy
the minimum amount of energy needed to a reaction to happen
Concentration/Pressure
increases the particles per unit volume which causes more frequent collisions
Catalyst
speeds up a reaction without being used in the reaction itself, lowers the activation energy, causing a higher proportion of successful collisions
Heat Energy
mass x 4.2 x change in temperature
Electrode
something that conducts electricity
Efficiency
how much something can produce compared to the theoretical output
Flammable
something that can burn
Renewable
something that can be used repeatedly and won’t run out
Combustion
when a fuel reacts with oxygen
Structure
what things look like when joined together
Bonding
how particles join up
Ionic Bonding
how metals and non-metals join
Covalent Bonding
how non-metals join
Metallic Bonding
how metals join
Dot-and-Cross Diagrams
a simplified diagram to explain ionic bonding using dots and crosses for electrons
Immiscible
does not mix with
Intermolecular
between molecules
Graphene
a single thickness of carbon atoms
Carbon Nanotube
a tube of graphene
Fullerene
a generic name for molecules made of carbon, such as buckminsterfullerene
Alltropes
structurally different forms of the same element
Bonding
what holds particles together
Structure
the organisation of particles
Electrostatic
the overall word for positive and negative attraction
Electron Configuration
how electrons are laid out on energy levels or shells
Monatomic
atoms that exist as individual atoms and do not form chemical bonds with each other or other elements
Diatomic
atoms that exist in pairs
Triatomic
atoms that exist in groups of three
Tetratomic
atoms that exist in groups of four
Cations
positive ions
Anions
negative ions
Anode
positive electrode, attracts anions
Cathode
negative electrode, attracts cations
Electrolyte
a liquid with free moving electrons that conducts electricity
Electrode
a conductor through which electricity enters or leaves something
Electrolysis
when an electric current flows through a liquid and creates chemical changes
Spectator Ion
an ion unaffected by electrolysis
Brine
a solution of salt in industry
Spectator Ion
an ion unaffected by electrolysis
Silicon Dioxide
sand
Pangaea
the original supercontinent which broke up into the tectonic plates
Acid Clouds
soluble clouds containing sulphur, which fall as acid rain
Sulphuric Acid
a weak acid (H2SO4)
Acid Rain
rain containing sulphuric acid which lowers the pH of lakes, rivers and soils around the globe
Acidosis
a disease where an organism’s pH goes too low
Alkadosis
a disease where an organism’s pH goes too high
Paraffin Wax
C20H42
Micron
millionth of a metre
Decimetre
one tenth of a metre
The Avogadro number
6.02x10^23
the amount of particles in 1g of hydrogen
Methane
a hydrocarbon with one carbon
Ethane
a hydrocarbon with two carbons
Propane
a hydrocarbon with three carbons
Butane
a hydrocarbon with four carbons
Pentane
a hydrocarbon with five carbons
Sextane
a hydrocarbon with six carbons
Heptanes
a hydrocarbon with seven carbons
Octane
a hydrocarbon with eight carbons
Nonane
a hydrocarbon with nine carbons
Decane
a hydrocarbon with ten carbons
Organic Chemistry
the chemistry of carbon-containing compounds
Alkane
compounds made from the simplest hydrocarbons
Homologous Series
the sequence of hydrocarbons
Fractional Distillation
holes in sedimentary rock where crude oil is formed
Crude oil
a substance formed in rock that can be separated out into naphtha, diesel, petrol and bitumen
Fractional Distillation
allows separation of substances
Pores
holes in sedimentary rock where crude oil is formed
Carbohydrates
oxygenated hydrocarbons
Oil Refinery
where fractional distillation happens and crude oil is separated out into molecules of similar sizes
Bubble Trap
parts of the fractional tower that slows down molecules
Alkenes
hydrocarbons containing double bonds
Complete Combustion
combustion that only produces carbon dioxide and water
Incomplete Combustion
combustion where there is not enough oxygen, producing carbon monoxide
Ethene
the simplest alkene, C2H4
Volatility
tendency a substance has to turn into a gas
Viscosity
how easily a substance a substance flows
Saturated Hydrocarbons
a hydrocarbon containing only single bonds
General Equation
algebraic equation to explain a trend
Cracking
reaction used in the oil industry to break down large hydrocarbons into smaller more useful ones
Thermal Decomposition
the breakdown of a compound by heating it
Unsaturated Hydrocarbons
a hydrocarbon whose molecules contain at least one double bond
Dodecane
a hydrocarbon with 12 carbon atoms
Saturated
a molecule with only single bonds
Unsaturated
a molecule with double bonds
Suckback
when air is sucked back into a test tube
Pentacosane
alkane with 25 carbons
Potassium Chloride
KCl, used in fertilisers
Sodium Nitrate
NaNO3, used for preserving sausages and ham
Table Salt
calcium chloride, CaCl2
Ammonium Nitrate
NH3NO3, used in fertilisers, does not contain a metal
Copper Sulphate
CuSO4, used in pesticides
Mercury Chloride
HgCl, used in pesticides
Plaster of Paris
Calcium Sulphate, CaSO4
Barium Sulphate
BaSO4, taken by patients before x-rays
Sodium Chloride
NaCl, used for preserving sausages and ham and flavouring food
Sodium Fluoride
NaF, used in toothpaste
Saltpetre
KNO4
Calcium Sulphate
CaSO4, used in plaster casts
Potassium Nitrate
KNO4, used in fireworks
Sodium Chloride
Na2O
Iron Chloride
FeCl3
Calcium Nitrate
Ca(NO3)2
Calcium Phosphate
Ca3(PO4)2
Acid + metal
salt + hydrogen
Acid + metal oxide
salt + water
Acid + metal hydroxide
salt + water
Acid + metal carbonate
salt + water + carbon dioxide
Magnesium Chloride
MgCl2
Magnesium Nitrate
Mg(NO3)2
Magnesium Sulphate
MgSO4
Sodium Sulphate
Na2SO4
Calcium Chloride
CaCl2
Copper Chloride
CuCl2
Copper Phosphate
Cu3PO4
Lithium Sulphate
Li2SO4
Sodium Phosphate
Na3PO4
Sodium Sulphate
Na2SO4
Zinc Chloride
ZnCl2
Zinc Nitrate
Zn(NO3)2
Aqueous
dissolved in water
Parallelopiped Crystals
crystals in the shape of six-sided parallelograms
pH
power of hydrogen
Ammonia
NH4NO3
Carbonic Acid
H2CO3
Hydrogen Peroxide
H2O2, forms a liquid at room temperature
Endothermic Reaction
reactions that cause a decrease in temperature, take energy in, and form bonds
Exothermic Reaction
reactions that cause an increase in temperature, release energy, and break bonds
Sulphuric Acid
a weak acid, H2SO4
Calorimetry
the science of measuring changes in state variables through heat transfer
Inert
unreactive
Helium
used to fill balloons and air ships as it is lighter than air
Neon
used for signs and lights
Argon
used to fill light bulbs as it doesn’t react with the Tungsten filament
Krypton
used to fill double glazing as it is a good insulator
Xenon
used for lasers, car headlights and anaesthetic
Radon
used in radiotherapy to cure cancer
Halogens
groups of seven toxic non-metals elements that have coloured vapours, with low melting and boiling points and are poor conductors
Fluorine
gas at room temperature, used to prevent tooth decay, processes nuclear fuel
Chlorine
gas at room temperature, used to make disinfectants and antiseptics
Bromine
liquid at room temperature, used in leaded petrol, medicines and photography
Iodine
solid at room temperature, used in animal food supplements
Astatine
solid at room temperature
Extrapolate
extending a curve on a graph
Alkali Metals
group of metals on the left hand side
Water
H2O
Cyclohexane
C6H12, used for dissolving halogens
Electrochemistry
chemistry of electrolysis
Monomer
small molecules that join together to form chains to make polymers
Polymer
molecules made out of long chains of hundreds of monomers, eg DNA, proteins
Repeating Unit
the bit of the polymer that repeats, which is different from the monomers as it breaks their double bond
Plastics
synthetic polymers shaped by heat or pressure
Natural Polymers
naturally-occurring polymers
Synthetic Polymers
manmade polymers
Polymerisation
the process by which polymers form
Styrene
a hydrocarbon with abnormal structure
Polystyrene
polymer made of sytrene
Polyethene
polymer made of ethene
Polypropene
polymer made of propene
Vinyl Chloride
H2C=CHCl
Polyvinylchloride
PCV, polymer made of multiple vinyl chloride monomers
Ester
monomers that join together to make polyester
Polyester
polymer made of multiple ester molecules
Anhydrous
without hydrogen