Flashcards in Unit 2 Deck (60)
What is a homologous series?
A family of compounds with
same general formula
similar chemical properties
a trend in physical properties
Name 5 homologous series
Alkanes, Alkenes, cycloalkanes, alkanols and alkanoic acids
In a homologous series, what trend in physical properties is often seen?
Increasing number of carbon atoms leads to increasing melting and boiling points.
What is a hydrocarbon?
A compound containing only hydrogen and carbon atoms
Compare the chemical and physical properties of C6H14 and C12H26
Same homologous series so similar chemical properties. The C12H26 is likely to have higher melting and boiling points than C6H14. It will therefore be less flammable. The longer chain C12H26 will be more viscous (thick) and the shorter one C6H14 more runny.
What is saturated compound?
One containing only single carbon to carbon bonds.
What is an unsaturated compound?
A compound containing at least one carbon to carbon double bond.
How do you test for a double bond?
A compound with a double bond will rapidly decolourise bromine water.
What is the molecular formula of a compound?
Each element written with number of how many there are in the molecule.
What is the structural formula of a compound?
A formula showing all the covalent bonds as sticks.
What are isomers?
Molecules with the same molecular formulae but different structural formulae.
Do isomers have different physical properties?
Name a 6 carbon isomer of hexene in a different homologous
What are alkanes and what is their general formula?
general formula is CnH2n+2
What are cycloalkanes and what is their general formula?
Cyclic, saturated hydrocarbons
general formula is CnH2n
What are most alkanes used for?
What are most cycloalkanes used for?
Fuels or solvents
What is a fuel?
Something you can burn to get energy
How are alkanes named?
Use the prefix to give the number of carbons.
use ... ane at end to show it is saturated. Any branches are written at start with numbers to show which carbon they are on.
What are the prefixes for carbon chains 1 to 8
Meth = 1
eth = 2
prop = 3
but = 4
pent = 5
hex = 6
hept = 7
oct = 8
What is the name of an alkane containing three carbon atoms and no branches?
What is the name of an alkane containing four carbon atoms and one branch?
Is there a chemical called 1-methylpropane?
NO. Branches can't happen at the very end of a molecule. This substance would just be butane.
What are alkanes used for?
To make polymers(plastics) and alcohols.
What are alkenes and what is their general formula?
Unsaturated hydrocarbon containing the C=C double bond functional group. General formula is CnH2n
What is the name given to a reaction that gives out heat energy?
Name the alkene with five carbon atoms and the double bond between the first and second carbon atoms.
What type of chemicals are in crude oil?
IT is a mixture of hydrocarbons-mainly alkanes.
What type of reactions do alkanes undergo?