Chemistry From 4 & 5 : Definition list

Hi guys, cik e-ka share bukan satu, tapi dua set definition list untuk students kimia form 4 & form 5 sekalians, cik e-ka dah arrange to table form lg, so hampa print, lipat tiga, dah jadi nota poket! mudah kan ? ;) Goodluck semua ~

Chemistry Form 4 Definition List
Element – a substance consists of one type of atom.	Compound – a substance consists two or more elements that are chemically bonded(molecule or ions).	Atom – smallest particle of an element.
Molecule – a group of two or more atoms.	Ion – a positively charged / negatively charged particle.	Isotopes – atoms of the same element with same proton number but different nucleonnumbers.
Relative atomic mass of an element = the average mass of one atom of an element/((1/12) x the mass of one carbon-12 atom)	Relative molecular mass of an element = the average mass of one   atom of an molecule/((1/12) x the mass of one carbon-12 atom)	Molecule formula – compound shows the actual number of atoms of each element that are present in a molecule of the compound
Empirical formula – compound shows the simplest whole number ratio of atoms of each element in the compound	Mole – amount of substance that contains as many particles as the number of atoms inexactly 12 g of carbon-12 the symbol of mole is mol.	One mole – Avogadro constant – 6.02 x 1023
Group (Periodic Table) – vertical columns of element (similar chemical properties).	Periods (Periodic Table) – horizontal rows of element.	Valence electrons – electrons that occupy the outermost shell.
Ionic bond – bond formed through the transfer of electrons   between atoms of metal andnon-metal to achieve the stable octet electron arrangement.	Ionic compound – consist of positive ions and negative ions which are held by strong electrostatic forces of attraction.	Covalent bond – bond formed through the sharing of non-metal electrons to achieve the stable duplet or octet electron arrangement.
Covalent compound (also simple molecular structure) – consists of neutral molecules which are held by weak intermolecular forces (Van der Waals).	Alkali (base) – chemical substance which ionizes in water to produce hydroxide ions, OH-.	Acid – chemical substance which ionizes in water to produce hydrogen ions, H+ or hydroxonium ions, H3O+.
pH – degree of acidity or alkalinity of a solution. Scale ranges from 0 to 14.	pH value – measure of the concentration of hydrogen ions, H+.	Strong alkali – ionises (dissociates) completely in water to form hydroxide ions, OH- of high concentration.
Weak alkali – ionises (dissociates) partially in water to form hydroxide ions, OH- of low concentration.	Strong acid – ionises (dissociates) completely in water to form hydrogen ions, H+ of high concentration.	Weak acid – ionises (dissociates) partially in water to form hydrogen ions, H+ of low concentration.
Polymer – long chain molecules made up by monomer (repeating unit).

SPM Chemistry Form 5 Definition List
Effective collision (Collision theory) – collision that results   in a chemical reaction where the particles collide with the correct orientation and are able to achieve the activation energy.	Homologous series – organic compounds (families) with similar formulae and properties.	Catalyst – a chemical that alter the rate of reaction.
Positive catalyst – increases the rate of reaction & lower the activation energy.	Negative catalyst – decreases the rate of reaction & higher the activation energy	Organic compounds – carbon-containing compound. Carbon atoms form covalent bonds.
Inorganic compounds – compounds from non-living things which do not contain the element carbon.	Saturated hydrocarbons – hydrocarbons containing only single bonds between all carbon atoms.	Unsaturated hydrocarbons – hydrocarbons containing at least one carbon-carbon doubleor triple bond.
Esterification – esters are produced	Vulcanisation – process which makes the natural rubber harder and increases its elasticity by adding sulphur.	Redox reaction – chemical reactions involving oxidation and reduction occurring simultaneously.
Flavouring – improve the taste or smell of food and restore taste loss due to food processing.	Stabilisers – help to mix two liquids that usually do not mix together so that they form an emulsion.	Thickeners – substances that thicken food and give the food a firm, smooth and uniform texture.
Precipitation – the heat change when one mole of a precipitate is formed from their ions in aqueous solution.	Displacement – the heat change when one mole of a metal is displaced from its salt solution by a more electropositive metal.	Neutralisation – the heat change when one mole of water is formed from the reaction between an acid and an alkali.
Combustion – the heat change when one mole of a substance is completely burnt in oxygen under standard conditions.