A | B |
-CHO is the functional group of | an aldehyde |
>C=O is the functional group in a | ketone |
CH3CHO is called | ethanal |
CH3.CO.CH3 is called | propanone |
CH3.CH2.CHO is called | propanal |
CH3.CH2.CO.CH3 is called | butanone |
CH3.CH2.CH2.CO.CH3 is called | pentan-2-one |
CH3.CH2.CH2.CHO is called | butanal |
An aldehyde grouping is only found on | the end of a chain |
a ketone grouping is only ever found in | the middle of a chain |
CH3.CHO + Fehlings & heat observation | turns from blue solution to red ppt |
CH3.CHO + Fehlings reaction type is | redox |
In redox reaction aldehydes are | reductants (reducing agents) |
CH3.CO.CH3 + Fehlings & heat | no reaction |
CH3.CHO + ammoniacal AgNO3 | forms silver mirror |
CH3.CO.CH3 + ammoniacal AgNO3 | no reaction between CH3.CO.CH3 and AgNO3 |
CH3.CHO + K2Cr2O7 & acid - heat under reflux observation | changes orange to green |
CH3.CHO + K2Cr2O7 & acid - heat under reflux product is | CH3COOH |
CH3.CHO + 2,4 ditrophenylhydrazine | yellow ppt |
with 2,4 dinitrophenylhydrazine ..... | CH3.CO.CH3 gives a yellow ppt |
aldehyde & ketones with 2,4 dinitrophenylhydrazine reaction type is | addition and elimination (of H2O) |
CH3.CHO + HCN forms | CH3.CHOH(CN) |
CH3.CHO + HCN reaction type | addition |
CH3.CO.CH3 + HCN forms | CH3.COH(CN).CH3 |
CH3.CHOH(CN) exists as optical isomers because | it has a chiral centre (an asymmetric carbon atom) |
A feature of molecules that have a chiral centre (an asymmetric carbon atom) is | they have 4 different groups on one carbon |
optical isomers are mirror images which | are not superimposable |
optical isomers have the same chemical properties but they | turn the plane of plane polarised light in opposite directions |
When CH3.CHO is reacted with HCN the resulting solution is not optically active because | the two isomers of CH3.CHOH(CN) have been formed in equal concentrations |
CH3.CHO + LiAlH4 forms | CH3.CH2OH |
LiAlH4 - essential conditions | in dry ether |
LiAlH4 is a | reducing agent |
CH3.CO.CH3 + LiAlH4 forms | CH3.CHOH.CH3 |
CH3.CH2OH | a primary alcohol |
CH3.CHOH.CH3 or any compound containing >CHOH is classed as | a secondary alcohol |
CH3.CO.CH3 & CH3.CHO & CH3.CH2OH all react with NaOH and I2 forming (observation) | a pale yellow ppt with an antiseptic smell |
CH3.CO.CH3 & CH3.CHO & CH3.CH2OH with NaOH + I2 product is | triiodomethane (iodoform) |
triiodomethane (iodoform) is formed when a | an alcohol, aldehyde or ketone molecule contains CH3.CO |
NaOH & I2 with CH3.CH2.CH2OH | no iodoform (no CH3.CO!!) |
NaOH & I2 with CH3.CHOH.CH3 | iodoform forms (CH3.CO!!) present |