intro to organic chemistry Flashcards
what is meant by the ‘general formula’ ?
-shows the number of atoms of each element in a substance which has n carbons.
- all the molecules in a homologous series have the same general formula
- the algebraic formula
general formula for alkenes
CnH2n
general formula for alkanes
CnH2n+2
general formula for alcohols
cnH2n+1OH
what is meant by the ‘ molecular formula ‘ ?
formula that gives the actual number of atoms of each element in a molecule. e,g C4H10
what is meant by the ‘empirical formula’ ?
the simplest whole number ratio of atoms in a compound
e,g C4H10 = C2H5
what is meant by the ‘structural formula ‘?
shows how the atoms are joined together in a molecule without showing each bond
e,g CH3CH2CH2CH3
what is meant by the skeletal formula ?
shows the bonds of the carbon skeleton only.
- lines represent bonds
- each point represents a carbon atom. all functional groups are shown but not hydrogens
what is meant by the displayed formula ?
shows all the bonds and atoms in a molecule
what is meant by a homologous series ?
a family of compounds with the same general formula and similar chemical properties
what do homologous series of a group of compounds have ?
same functional group and general formula
what happens in a homologous series to each member in term of C and H atoms ?
each member differs by the addition of a CH2 and there is a gradual change in physical properties
what is the suffix of an aldehyde ?
-al
e.g propanal
what is the suffix of ketones ?
-one
e.g propanone
suffix of carboxylic acids ?
-oic acid
e.g butanoic acid
