Chemistry Words
- Products The substances produced during a chemical reaction
- Properties The properties of a substance describe what it is like eg reactive, hard
- Proton One of the the sub atomic particles found in the nucleus. Protons have a positive charge.
- Proton number Also known as the atomic number, it tells you the number of protons in the nucleus of an atom
- Quarries Places where we can dig a substance, usually a rock, out of the ground.
- Quicklime Calcium oxide. A substance made by the thermal decomposition of calcium carbonate (limestone)
- Rate of reaction How fast a chemical reaction takes place
- Reactants The substances used up during a chemical reaction
- Reaction When chemicals react or break apart
- Reactivity How easily a substance burns or reacts with other chemicals like water and acid
- Reactivity series A list of elements in order of how reactive they are.
- Reduction When oxygen is removed from a compound or when an atom or ion gains electrons
- Relative atomic mass The relative atomic mass, Ar, is the average mass of the atoms of an element compared to carbon-12
- Relative formula mass The relative formula mass, Mr, is the mass of one mole of a substance (in grams)
- Renewable Supplies of a renewable substance will not run out for example biofuels
- Retention time In gas chromatography, the retention time is a measure of the time taken for a solute to pass through a chromatography column.
- Reversible reaction A chemical reaction that can go both ways for example reactants form the products and the products form reactants
- Rust Iron oxide
- s An abbreviation that stands for "solid"
- Salt A compound formed when an acid is neutralised by an alkali or base
- Saturated hydrocarbon An alkane - a hydrocabon that only has single bonds
- Scale Heating temporarily hard water decomposes the hydrogen carbonate ions to from limescale or scale.
- Scum Scum is formed when soap reacts with calcium ions or magnesium ions.
- Sediment Small bits of solid that settles at the bottom of a liquid
- Sedimentary rock Rocks formed from layers of sediment for example limestone
- Shape memory alloy An alloy which returns to its narmal shape after bending
- Shape memory alloys A metallic material which has one shape at a low temperature and a different shape at a higher temperature
- Shell Shells are made from calcium carbonate
- Slaked lime Solid Calcium hydroxide
- Smart material Smart materials have properties that react to changes in their environment
- Smelting Extracting a metal from its ore by heating and melting
- Soapless detergent A petroleum based detergent which reacts with the calcium ions or magnesium ions in hard water but does not form scum
- Sodium chloride NaCl, sodium chloride is the salt used in cooking to flavour foods
- Soft water Soft water does not contain any calcium ions, magnesium ions or hydrogen carbonate ions so lathers readily.
- Solid One of the three states of matter, along with liquid and gas
- Soluble Able to dissolve
- Solution A mixture formed when a substance (the solute) dissolves in a solvent (often water)
- Stainless steel An alloy of iron that does not corrode very easily.
- State symbol State symbols are used in chemical equations to describe the physical state a reactant or product is in when the reaction occurs
- Steam The vapour formed when water is boiled
- Steel An alloy of iron.
- Strong acids Strong acids are fully ionised in solution
- Structural formula A way of showing the structure of molecules using symbols for the atoms and lines to represent the chemical bonds between them
- Symbol A short way of writing an element eg C = carbon, H = hydrogen, N = nitrogen
- Symbol equation A symbol equation shows the reactants and products of a chemical reaction using their formulas and state symbols
- Tectonic plate A section of the Earth's crust
- Temporary hard water Temporary hard water contains hydrogen carbonate ions (HCO3) 2-.
- Thermal decomposition A reaction that uses thermal (heat) energy to break down a substance into new substances
- Thermosetting polymer A thermosetting polymer has cross links between the hydrocarbon chains which makes the polymer more heat resistant. Thermosetting polymers cannot be remoulded.
- Thermosoftening polymer Thermosoftening polymers do not have cross links so when heated the plastic can be reshaped and cooled to a new shape.
- Titanium A transition metal which has high strngth, low density and good resistance to corrosion.
- Titration Titration is a method used to determine the concentration of an unknown acid or alkali
- Transition metal Metals in the central block of the periodic table, they do not belong to any of the groups.
- Universal indicator A indicator used to determine the pH of a substance
- Unreactive Not able to take part in a chemical reaction
- Unsaturated Inan unsaturated hydrocarbon molecule, two of the carbon atoms are linked by a double bond.
- Vapour a gas produced when a liquid evaporates
- Viscous If a hydrocarbon is viscous, it has a thick sticky consistency.
- Volatility If a hydrocarbon is violatile, it evaporates easily
- Weak acids Weak acids partialy ionise in solution
- Wegener, Alfred (1880-1930) The first person to develop the idea of continental drift, where a super continent, Pangaea has moved to form several smaller continents.
- Word equation A word equation shows the reactants and products of chemical reactions using their names not chemical symbol
- Yeast micro-organisms which produce alcohol from a sugar and water mixture
- Yeasts micro-organisms which produce alcohol from a sugar and water mixture
- Yield The amount of an agricultural product produced