A measurement is considered to be accurate if it is judged to be close to the true value
A sour substance which can attack metal, clothing or skin. When dissolved in water, its solution has a pH value less than 7. Acids are proton (H+ ion) donors.
The minimum energy needed for a reaction to take place.
Elements in Group 1 of the periodic table e.g. lithium (Li), sodium (Na), potassium (K)
Its solution has a pH value more than 7
Saturated hydrocarbon with the general formula CnH2n+2, e.g. methane, ethane and propane
Unsaturated hydrocarbon which contains the carbon-carbon double bond. Its general formula is CnH2n, e.g. ethene C2H4.
A mixture of metals (and sometimes non metals). For example brass is a mixture of copper and zinc.
A low density, corrosion-resistant material used in many alloys, including those used in the aircraft industry.
An oxide that displays both acidic and basic properties
Describes a substance that does not contain water.
The positive electrode in electrolysis
Results that do not match the pattern seen in the other data collected or are well outside the range of other repeat readings. They should be retested and if necessary discarded.
The mixture made by adding a soluble solution to water.
The relatively thin layer of gases that surround planet Earth.
A symbol equation in which there are equal numbers of each type of atom on wither side of the equation.
A chart with rectangular bars with lengths proportional to the values that they represent. The bars should be of equal width. Also called a bar graph.
The oxide, hydroxide or carbonate of a metal that will react with an acid, forming a salt as one of the products. (If a base dissolves in water it is called an alkali). Bases are proton (H+ ion) acceptors.
Materials that can be broken down by microorganisms.
Fuel for cars made from plant oils