Definitions 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 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= Distances 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, ie |
—NH
Tertiary amine
Three carbon atoms directly bonded to the nitrogen atom ie. |
—N
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