Aldehydes and ketones (Lab) Flashcards
What is the functional group of aldehyde?
R-CHO
The simplest member of RCHO
HCHO = methanal or formaldehyde
Which is more reactive: Aldehyde or ketone?
Aldehyde
What is the formula of formaldehyde?
HCHO
What do you call HCHO dissolved in water? This is also often used to embalm dead bodies
Formalin
It is an aldehyde that is colorless wuth a pungent smell, irritating odor
HCHO
An aldehyde with a chico-like odor and is soluble in water
CH3CHO
An aldehyde with a clear colorless liquid with an almond-like smell. It is often used as food additive
Benzaldehyde
The simplest aromatic aldehyde
Benzaldehyde
What is the formula of benzaldehyde?
C6H5CHO
True or false: Aldehydes and ketones are functional isomers
True
What is the functional group of ketone?
R-CO-R
It resists polymerization and is not easily oxidized
Ketones
It gives negative results with Fehling’s, Tollen’s, and other mild oxidizing agents
Ketone
An organic compound with the formula (CH3)2CO
Acetone
It is the simplest and smallest ketone
Acetone
It is a clear colorless flammable liquid with a pleasant, somewhat fruityodor, melting at -95.4 °C and boiling at 56.53 °C w/ sharp biting taste
Acetone
A type of ketone that is highly flammable & burns with luminous flame
Acetone
The positive result of 2,4-dinitrophenyl hydrazine test (DNP)
yellow to orange to red ppt
The positive result of NaHSO3 Test
white crystalline ppt
What is the composition of schiff’s test reagent?
fuchsin dye + SO2
What is the positive result of schiff’s test?
purple (magenta) in aliphatic & aromatic aldehydes; pale pink with ketones
What happens to schiff’s test if aldehyde is present?
The color is magenta
What is the composition Fehling’s test?
A = CuSO4 (blue solution)
B = Na-K tartrate or Rochelle salt
The positive result of Fehling’s test
brick red ppt. , Cu2O
What is the role of aldehyde in fehling’s test?
Reducing agent
What is the composition of tollen’s test?
AgNO3 + NH4OH
The positive result of tollen’s test
Silver mirror, Ag0
The appearance of red colorations shows presences of _____ in sodium nitroprusside test
Ketone
The formula of sodium nitroprusside test
(Na2 [Fe(CN)5NO].2H2O)
The positive result of sodium nitroprusside
blood red that changes to wine red upon the addition of acetic acid
The positive result of Iodoform test
Yellow ppt
The result of autooxidation of benzaldehyde
White crystals
