Terms Flashcards
(38 cards)
Base peak
Peak of greatest abundance in a mass spectrum.
Molecular ion peak
A peak produced by an ion formed by the removal of one electron from a molecule.
M+1 peak
A peak produced by a molecular ion with an increased mass due to the presence of one carbon-13 atom.
Fragmentation ion
A positively charged ion produced when the molecular ion breaks apart.
Low resolution nmr
A spectrum which does not show the spin-spin splitting pattern.
High resolution nmr
A spectrum which does show the spin-spin splitting pattern.
Doublet
A signal which appears as a pair of lines of equal intensity.
Triplet
A signal which appears as three lines in the approximate intensity ratio (1:2:1).
Quartet
A signal which appears as four lines in the approximate intensity ratio (1:3:3:1).
Back titration
Method where an excess of a reagent is reacted with a sample. The unreacted reagent is then determined by titration.
Rf values
Retardation factor, this is calculated using the expression:
Rf = distance moved by spot / distance moved by solvent
Retention time
The time taken from injection until a component reaches the detector.
Transition metal
An element which forms at least one stable ion with a partially filled d-subshell.
Complex
A central metal atom or ion with ligands bonded by co-ordinate bonds.
Ligand
An ion or molecule with a lone pair of electrons which forms a co-ordinate bond with a central metal atom or ion in a complex.
Co-ordination number
The number of co-ordinate bonds to a central metal atom or ion in a complex.
Monodentate
A ligand which uses only one lone pair of electrons to form a co-ordinate bond with a central metal atom or ion in a complex.
Bidentate
A ligand which uses two lone pairs of electrons to form two co-ordinate bonds with a central metal atom or ion in a complex.
Polydentate
A ligand which uses many lone pairs of electrons to form more than two co-ordinate bonds with a central metal atom or ion in a complex.
Standard electrode potential
The potential difference measured when a half-cell is connected to the standard hydrogen electrode under standard conditions.
e.m.f.
The potential difference measured when two half-cells are connected.
Primary amine
Only one carbon atom directly bonded to the nitrogen atom and therefore has the (-NH2) group.
Secondary amine
Two carbon atoms directly bonded to the nitrogen atom.
Tertiary amine
Three carbon atoms directly bonded to the nitrogen atom.
