Study Set Content:
Silver ions in the presence of hydroxide ions come out of solution as a
brown precipitate of silver(I) oxide, Ag2O(s)
Silver ions in the presence of hydroxide ions come out of solution as a brown precipitate of silver(I) oxide, Ag2O(s). This precipitate dissolves in aqueous ammonia, forming the
diamminesilver(I) ion, [Ag(NH3 )2 ]+
• Barfoed’s test makes use of
Barfoed’s solution
Barfoed’s test makes use of Barfoed’s solution which contains
copper acetate in the dilute acetic acid.
do not react with Tollens' reagent.
Ketones
In Barfoed’s test, the reducing monosaccharide is
oxidized
In Barfoed’s test, the reducing monosaccharide is oxidized by the
copper ion
In Barfoed’s test, the reducing monosaccharide is oxidized by the copper ion in the solution to form a
carboxylic acid and copper (I) oxide
In Barfoed’s test, the reducing monosaccharide is oxidized by the copper ion in the solution to form a carboxylic acid and copper (I) oxide which results into the formation of a
red colored precipitate
Barfoed's reagent reacts with monosaccharides to produce (blank) at a faster rate than disaccharides do
cuprous oxide
s most commonly used to distinguish pentoses from hexoses
Bial’s Test
is most commonly used to distinguish aldoses and ketoses.
Seliwanoff’s Test
Bial’s solution contains
orcinol, hydrochloric acid and ferric chloride
In the Bial’s test, pentoses react with the Bial’s reagent and convert it into furfural derivatives as a result of dehydration by
HCl.
Seliwanoff’s test makes use of
Seliwanoff’s reagent
Seliwanoff’s test makes use of Seliwanoff’s reagent which contains
0.5g of resorcinol per liter in 10% HCl.
Then, orcinol and furfural condense in the presence of ferric ion to form a
blue – green or bluish colored compound.
In the Seliwanoff’s test, ketoses react with the HCl of the Seliwanoff’s reagent which yields furfural derivatives as a result of
dehydration.
Then, resorcinol and furfural react to give a (blank) to the solution.
deep red color
Is one in which concentrated HNO3 is heated along with an aldose sugar to give a dicarboxylic acid.
Mucic acid test
