Definitions (Understand) Flashcards
Atomic number
the number of protons in the nucleus of an atom
Relative formula mass
the weighted mean mass of a formula unit compared with one-twelth of the mass of an atom of carbon 12
Relative molecular mass
the weighted mean mass of a molecule compared with one-twelfth of the mass of an atom of carbon-12.
Mole
the amount of substance containing as many particles as there are carbon atoms in exactly 12g of carbon-12 isotope
Molar mass
The mass of one mole of any substance, expressed in grams per mole.
Empirical formula
the simplest whole number ratio of atoms of each element in a compound
Molecular formula
the number of atoms of each element in a molecule
Lone pair
an outer-shell pair of electrons that is not involved in chemical bonding
Bonded pair of electrons
A pair of electrons shared between two atoms to make a covalent bond.
Permanent dipole
a small charge difference across a bond resulting from a difference in the electronegativities of the bonded atoms
Polar bond
A covalent bond with a permanent dipole
Polar molecule
a molecule with an overall dipole, taking into account any dipoles across bonds
Alkyl group
an alkane with a hydrogen atom removed, e.g. CH3, C2H5; alkyl groups are often shown as R
Alicyclic
Contains carbon atoms joined together in a ring that is not aromatic.
Aliphatic
Contains carbon atoms joined together in straight or branched chains.
Aromatic
Containing one or more benzene rings
Saturated
Containing single bonds only
Unsaturated
Containing a multiple carbon-carbon bond