4NA - Organic chemistry Flashcards
(25 cards)
which homologous series does the C=C functional group belong to
alkene
do alkanes have a functional group
no
what are hydrocarbons?
organic compounds that contain hydrogen and carbon ONLY
what are the common characteristics among members of a homologous series
same functional group
similar chemical properties
gradual change in physical properties from one member to the next
differ from one member to the next by a CH2 unit
share the same general formula
how many carbon atoms does an organic compound have if its name begins with the prefix ‘prop-‘
3
how many carbon atoms does an organic compound have if its name begins with the prefix ‘meth-‘
1
how many carbon atoms does an organic compound have if its name begins with the prefix ‘eth-‘
2
what method/technique is used to separate the fractions of petroleum
fractional distillation
state the physical property that is used to separate the fractions of petroleum
the fractions have different boiling points
which fraction of petroleum is used for paving road surfaces
bitumen
which petroleum fraction has a lower boiling point - kerosene or naphtha
naphtha
[fractions higher up in the column have lower bp than those lower]
which petroleum fraction is used as chemical feedstock
naphtha
what is the general formula for alkanes
CnH2n+2
what is the chemical formula for ethane
C2H6
why are alkanes known as ‘saturated hydrocarbons’
they contain only single C-C covalent bonds
why do the the mp/bp of alkanes increase down the homologous series (i.e. as molecular size of alkane increase)
stronger intermolecular forces of attraction between alkane molecules
how does the viscosity of alkanes change
becomes more viscous as the alkane molecular size increase
what are the products of complete combustion of alkanes
carbon dioxide and water/water vapour
what is the general formula for alkenes
CnH2n
why are alkenes known as ‘unsaturated hydrocarbons’
contain one or more C=C [or carbon-carbon double bond] (reject ‘carbon double bond’)
state the catalysts used in catalytic cracking
aluminium oxide or silicon(IV) oxide (or silicon dioxide)
what are the possible products of catalytic cracking
smaller alkenes and smaller alkanes and hydrogen gas
what are the conditions for hydrogenation of alkenes
200 degree Celsius and Ni catalyst
what is a major application of hydrogenation
to make margarine from vegetable oil
