EXPERIMENT 7 : ALDEHYDE AND KETONE Flashcards
C=O
Carbonyl
Is Oxygen more electronegative than Carbon?
True
Where is Aldehyde located?
Terminal part
Where is Ketone located?
Middle, indicates 2 R groups
Aldehydes and some ketones are often recognizable by their _______ smells.
sweet
Chanel No. 5 is expensive due to tedious process of getting ?
aldehyde and ketone
vanilla flavoring
vanillin
almond flavoring
benzaldehyde
cinnamon flavoring
cinnamaldehyde
aside from being a flavorant, vanillin is also used in?
parkinsons disease
hypertension
benzaldehyde is usually seen in what species?
prunus
prunus species
almonds, apples, peaches, cherries, apricot
clove flavoring
2-Heptanone
butter flavoring
Butanedione
spearmint flavoring
Carvone
primary alcohol oxidizes to ?
aldehyde
secondary alcohol oxidizes to ?
ketone
aldehyde can be further oxidized to carboxylic acid if?
the oxidizing agent is strong
what are the catalyst in dehydrogenation of primary alcohol?
copper / nickel
Cu / Ni
temperature of the catalyst Cu / Ni in dehydrogenation
250 - 329°C
General preparations of aldehyde
- Hydrolysis of geminal dihalide
- Hydration of alkynes
Hydrolysis of geminal dihalide is an organic reaction.
Hydrolysis of geminak dihalide with water molecule / hydroxylic ion yields ?
ketone or aldehyde
mercuric sulfate formula
HgSO4
borane formula
BH3
THF meaning
Tetrahydrofuran
Specific preparation of aldehyde
Methanal
Ethanal
Oxidation of methanol
Methanal
Ethanal is the oxidation of ethanol and the hydration of ?
Acetylene
Net process wherein there is protonation.
Tautomerization
Acetone preparations
Oxidation of propan-2-ol
Distillation of solid Calcium acetates
Neither aldehydes nor ketones possess the ability to H-bond with other molecules like themselves. However, they can form H-bond with ?
water molecule
Boiling points for aldehydes and ketones are (higher/lower) than for alcohols of similar molar mass.
LOWER
Generally the boiling point of aldehydes and ketones increases with increase in ?
molecular weight
The lower members (up to 4 carbons) of aldehydes and ketones are soluble in water due to ?
H-bonding
The ______ members do not dissolve in water because the hydrocarbon part is larger and resists the formation of hydrogen bonds with water molecules.
higher
PCC meaning
pyridinium chlorochromate
(mild oxidant)
acetylene + water
ethanal / acetaldehyde
ethenol is also known as?
vinyl alcohol
Organic reaction without active jydrogen that undergoes redox reaction under a presence of strong base.
Cannizzaro Reaction
4 Aldehydes without active Hydrogen.
Vanillin
Benzaldehyde
Siryngaldehyde
Formaldehyde
Note that most ketones and aromatic aldehydes will not react. Aliphatic aldehydes will only react.
(+) red ppt (aldehyde)
Benedicts Test (Reduction test)
Aldehyde + Benedicts Reagent =
Carboxylate Ion , RED ppt
In Benedict’s test, an aldehyde is oxidized to a carboxylic acid, while Cu2+ is reduced to give ?
red Cu2O(s)
reducing carbohydrates/sugars have ?
aldehydes
Reaction tests for the presence of primary alcohols, secondary alcohol and aldehyde.
Chromic acid test
In chromic acid test, (+) primary or secondary alc-2-3 secs formation of __________ suspension and disappearance of ____________
formation of cloudy blue green
disappearance of orange colored reagent
With aliphatic aldehydes, the solution turns cloudy in about __ seconds and the blue-green suspension forms within __ seconds.
5 seconds, cloudy
30 seconds, blue-green
In chromic acid test, a __________ color in either layer indicates a positive test.
Blue-green color
tollen’s test component
ammoniacal silver nitrate
Tollens’ reagent, which contains Ag+, oxidizes aldehydes but NOT ________.
Ketones
In tollen’s test, Ag+ is reduced to metallic Ag, which appears as a ______ in the test tube.
mirror
Aldehydes and ketones containing the CH3C=O group will give a positive result with the __________ reaction.
triiodomethane
Therefore, only aldehyde to give a positive result in Iodoform test is ______?
ETHANAL
Result in Iodoform Test?
pale yellow precipitate