Core Organic Chemistry Flashcards
3 reasons carbon can form so many compounds.
- can form 4 covalent bonds with other atoms
- can form single, double or triple bonds
- can bond to other c atoms to form chains
define hydrocarbon
A compound containing carbon and hydrogen only
define aliphatic
relating to or denoting organic compounds in which carbon atoms form open chains
define alicyclic
relating or denoting to organic compounds that combine rings and chains / cyclic and aliphatic properties
define aromatic
organic compounds containing a planar unsaturated ring of atoms which is stabilised by the bonds forming the ring. possibly including a benzene ring
define saturated
.a molecule or substance where the atoms are only linked with single bonds
define unsaturated
.a molecule or substance containing non-single bonds
define homologous series
a series of organic compounds which have the same functional group but with each succesive memberdiffering by one CH2
define functional group
a group of atoms responsible for the characteristic rections of a compound
General formula for alkanes
C(n)H(2n+2) (saturated chain)
General formula for cycloalkanes
CnH2n (saturated circle of bonds)
General formula for alkynes
C(n)H(2n-2) (includes a triple bond)
skeletal formula
A simplified organic formula with hydrogen atoms removed from alkyl chains leaving just carbon skeleton and associated functional groups
Displayed formula
The relative positioning of all the atoms in a molecule, including bonds between them
Alkane (formula of functional group)
C-C
Alkene functional group formula
C=C
Haloalkane functional group formula
R-I
R-Cl
R-Br
etc.
Alcohol functional group
- OH
- ol
Aldehyde functional group
R-C(-H)=O
Trigonal planar structure where R is a C chain or a hydrogen
-al
ketone functional group
R-C(-R)=O
R is only a C chain
-one
Carboxcylic acid functional group
R-C(-OH)=O
R is a H or a C chain
-oic acid
Define structural isomers
Same molecular formula but different Displayed formula
3 types of structural isomers
Chain isomer
-hydrocarbon chain may be branched or unbranched
-stem names for these isomers are different
Position isomer
- The hydrocarbon chain stays the same in these isomers but the position of the functional group is found at different points along the chain
- the numbers are different
Functional group isomer
-The functional group is different
-the prefix or suffix is different in the naming eg, cyclo- and -enes could have the same molecular formula
Define an Alkane
Saturated hydrocarbons
General hydrocarbon of formula CxHy combustion
CxHy + (x + 1/4y)O2 —–> xCO2 + 0.5yH2O
Why is incomplete combustion dangerous?
carbon monoxide is toxic and can cause death by preventing haemoglobin from carrying oxygen to respiring tissues
Because CO is colourless and odorless it can be difficult to detect
Why are yellow flames from Bunsen burners yellow?
The yellowness is caused by glowing soot particles indicating incomplete combustion, the outside of any glassware used will become blackened with soot.
Reaction of alkanes with halogens /HCl
Substitution reaction
CH4 + Br2 —–> CH3Br + HBr
UV light is required as it provides the energy to break initial bonds
Define a radical //notaion
A radical is a species with an unpaired electron
A dot similar to a bullet point after the element
Radical substitution 3 stages?
initiation, propagation, termination
Radical substitution, stages, info and equations
- = to the bullet point thingy
Initiation stage
initiation generates radicals for the reaction
Br2 —-UV—–> 2Br*
UV light provides energy required for the HOMOLYTIC bond breaking of Br-Br
Because the covalent bond between the Br’s contains two shared electrons, when this bond is broken both atoms recieve one of the two shared electrons. Giving both atoms an unpaired electron and creating radicals
Propagation stage
for every radical used in this reaction a new radical is produced.
Br* + CH4 —> HBr + CH3*
CH3* + Br2 —–> CH3Br + Br*
Termination stage 2 radicals combine to produce a product that is not radical CH3* + Br* -----> CH3Br Br* + Br * -----> Br2 CH3* + CH3* ------> C2H6
By reacting propane with bromine a chemist tried to make 1-bromo propane.
WHat mixture of products did he make and how were they formed?
1-bromopropane – formed by simple radical substitution
2-bromopropane – formed by substitution at a different point in the C chain
1,1(/1,2/1,3) -dibromopropane —was formed by further substitution
Hexane — when two C3H7* combined
1-bromohexane —- substitution of the hexane side product
2,3,5-tribromohexane – formed by multiple substitution of hexane side product
3 limitations of radical substitution
-Further substitution can occur
-Substitution at different points of C chain can occur
- C chain may change length / double
It is difficult to synthesis only 1 product
