Key Definitions Flashcards
Relative atomic mass.
The weighted mean mass of an atom of an element compared to 1/12th the mass of carbon-12.
Relative isotopic mass.
The mass of an atom of an isotope, compared with 1/12th the mass of an atom of carbon-12
Relative formula mass
The average mass of a molecule of formula unit compared to the mass of an atom of carbon - 12
Substitution
A chemical reaction during which a functional group is replaced by another functional group.
Saturated hydrocarbon
A hydrocarbon with single bonds only
Isotope
Different atoms of the same element with the same number of protons and electrons but a different number of neutrons.
Homologous series
A family of compounds with similar properties whose successive members differ by the addition of a CH2 group
Functional group
Part of the organic molecule that is largely responsible for the molecules chemical properties.
Aliphatic compound
Carbon atoms joined in branched or unbranched chains. Non aromatic.
Aromatic compound
Some or all of the carbon atoms are found in a benzene ring
Alicyclic compound
Carbon atoms joined to each other in a ring structure with or without branches.
Alkyl group
A group containing carbon and hydrogen only and branched from the parent Alkane chain
Saturated compound
A compound containing only single carbon bonds
Unsaturated
A compound containing at least one double or triple carbon -carbon bond.
Radical
A reactive atom or group of atoms with an unpaired electron.
Sterioisomerism
The same functional group but different arrangement of atoms in space.
Markonowikoffs rule
A hydrogen will be added to the carbon with the most hydrogens attached to it.
Structural isomer
Same molecular formula but different structural formula.
Electrophile
An atom or group of atoms attracted to an electron rich centre and accepts an electron pair.
Electronegativity
Ability of an atom to attract elect density towards itself in a covenant bond
Covenant bond
Attraction between a shared pair of electron and the positively charged nuclei of the atoms sharing the electrons.
Dipole
Separation of opposite charges
What is an acid?
An acid is a substance that, in aqueous solution, releases hydrogen ions. Proton donors.
What is the difference between an alkali and a base?
A base is a substance that can neutralise an acid. It accepts H+ ions. Proton acceptor.
An alkali is a base that can dissolve in water (polar). An alkali is a soluble base. It releases OH- Ions.
How is ammonia a base?
(NH3) ammonia produces hydroxide ions by reacting with water. The ammonium molecule accepts hydrogen ions in a reversible reaction.
Hydrated salt.
A salt that contained water as part of its structure in the crystal lattice.
