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What does Tollens reagent Fehlings solution 2 4-Dinitrophenylhydrazine and Benedicts solution test for and what are the results?
Wiki User
∙ 13y ago
Brady's reagent (2,4-DNP) forms a orange precipitate for all carbonyl compounds (C=O functional group), both aldehydes (primary) and ketones (secondary). However, recrystalisation of the orange precipitate gives characteristic melting points of the crystal for each carbonyl compound (therefore the presence of an orange precipitate indicates a carbonyl compound and the melting point of the crystallised precipitate indicates the type of carbonyl compound; aldehyde or ketone).
Tollen's reagent (diamminesilver nitrate solution) is reduced and forms a silver mirror when heated with an aldehyde. It distinguishes between aldehydes and ketones as ketones do not react (no silver mirror formed) as they can not be oxidised further.
Fehling's solution (copper II ions in sodium hydroxide) is reduced from a blue solution (Cu II ions) to a brick red precipitate (Cu I ions) when heated in the presence of an aldehyde. Ketones do not react as they can not be oxidised further.
The Benedict's test is used in organic chemistry to distinguish between reducing sugars (brick red precipitate formed) and non-reducing sugars (no reaction).
Wiki User
∙ 13y ago
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What compound can be oxidized by both Benedicts solution and Tollens reagent?
All the compounds having free aldehyde group as reducing sugars.
What happen when you react sugar like glucose and fructose with tollen' s reagent and the Fehlings solution?
Glucose oxidizes very quickly, and creates a silver mirror layer between the glucose solution and the Tollens' reagent. This is because of how the ketose reacts and reduces the silver molecules in Tollen's reagent.
What is the equation for the reaction between tollens' reagent and butanone?
Does not react. Because Tollens' reagent only works with aldehydes. Butanone is methyl ethyl ketone (MEK).
Is fructose gives positive test with tollens reagent?
no negative
Does the tollens test deal with alkenes?
No, the Tollen's Silver Mirror Test only confirms the presence of aldehydes.
explain using sample equation, the application of benedicts tollens and fehlings test in hospital?
wrt
What happens to aldehyde when it reacts with fehlings solution or tollens solution?
Aldehyde are oxidised to the corresponding carbonic acid by F.'s or T.'s agents. Ketone can not be oxidised.
What compound can be oxidized by both Benedicts solution and Tollens reagent?
All the compounds having free aldehyde group as reducing sugars.
What happen when you react sugar like glucose and fructose with tollen' s reagent and the Fehlings solution?
Glucose oxidizes very quickly, and creates a silver mirror layer between the glucose solution and the Tollens' reagent. This is because of how the ketose reacts and reduces the silver molecules in Tollen's reagent.
Is vanillin positive in tollens test?
No.While vanillin is an aldehyde, which should react with Tollens' reagent to precipitate silver metal, vanillin does not "pass" Tollens' test. Tollens' reagent is very basic (sodium or potassium hydroxide). Vanillin has a phenolic hydrogen (OH bonded to a phenyl ring) which is slightly acidic. Vanillin will react first with the excess hydroxide ions in solution to form a phenoxide salt, which will not participate in the silver-precipitating reaction.
When was Bernhard Tollens born?
Bernhard Tollens was born on 1841-07-30.
When did Bernhard Tollens die?
Bernhard Tollens died on 1918-01-31.
When did Hendrik Tollens die?
Hendrik Tollens died on 1856-10-21.
When was Hendrik Tollens born?
Hendrik Tollens was born on 1780-09-24.
What does modus tollens means in english?
Mudus Tollens = "the way that denies by denying"
Will CH3CHO react to tollens?
Tollens are chemical reagents that are commonly used to determine whether a known carbonyl containing compound is an aldehyde. It is stated that CH3CHO will not react to tollens at all.
What is the reaction of acetone and tollens reagent?
Tollens' reagent is used to determine whether a carbonyl containing compound is an aldehyde or a ketone. Acetone is a ketone so it will not readily react with Tollens' reagent.
