Users' questions

What is the formula for tollen reagent?

What is the formula for tollen reagent?

Tollens’ reagent (chemical formula Ag(NH3)2OH) is a chemical reagent used to distinguish between aldehydes and ketone functional groups along with some alpha-hydroxy ketones which can tautomerize into aldehydes.

What is fehlings reagent formula?

Fehling’s reagent (A) | CuH2O4S – PubChem.

What is Tollen’s reagent and Fehling solution?

Tollen’s test: this test is used to differentiate between a ketone and an aldehyde. In this test aldehyde is oxidised where as the ketone will not undergo oxidation. Fehling’s test: This test is used to detection of reducing sugar. It contain two solution Fehling’s solution A and Fehling’s solution B.

What is Fehling solution B formula?

The deep blue active ingredient in Fehling’s solution is the bis(tartrate) complex of Cu 2+. The net reaction between an aldehyde and the copper(II) ions in Fehling’s solution may be written as: RCHO + 2 Cu 2+ + 5 OH − → RCOO − + Cu 2O + 3 H 2O.

What is in Fehling’s solution?

Fehling’s solution is prepared by combining two separate solutions: Fehling’s A, which is a deep blue aqueous solution of copper(II) sulfate, and Fehling’s B, which is a colorless solution of aqueous potassium sodium tartrate (also known as Rochelle salt) made strongly alkali with sodium hydroxide.

Which type of aldehyde can give Fehling’s test?

Formaldehyde and acetaldehyde both have alpha hydrogen. Thus, both compounds will show positive Fehling’s test.

Which gives Fehling’s solution test?

The Glucose structure has an aldehyde group and due to which it gives a positive test for Fehling’s solution. Thus, the right answer is (B) Glucose.

What is Fehling A and Fehling B?

Fehling A is a blue-colored aqueous solution of copper (II) sulfate (CuSO4). Fehling B is a colorless aqueous solution of potassium sodium tartrate (KNaC4H4O6·4H2O, also known as Rochelle salt) in an alkaline base like sodium hydroxide (NaOH).

What is Fehling A and Fehling B solution?

What is the aim of Fehling’s test?

The Fehling test is used to differentiate between the presence of aldehydes and ketones in carbohydrates since, in this test, ketone sugars other than alpha-hydroxy-ketone do not react. In medical facilities, Fehling’s test is conducted to detect the presence of glucose in urine.

What gives Fehling test?

Fehling’s A solution is an aqueous solution of copper sulfate, whereas Fehling’s solution B is formed by alkaline sodium potassium tartrate. If an aldehyde or sugar molecule is the test solution, they form a reddish-brown chelated compound with Fehling’s reagent.

Why ketones do not give Fehling test?

The copper(II) complex in Fehling’s solution is an oxidizing agent and the active reagent in the test. Ketone does not react with the Fehling’s solution unless they are alpha-hydroxy ketones. Acetone is not alpha-hydroxy ketone so it will also not reduce the Fehling’s solution.

What is the formula for the Tollens reagent reaction?

The reaction that takes place during the Tollens’ Test is as follows: RCHO + 2[Ag (NH 3) 2]OH 🡪 RCOONH 4 +3NH 3 + 2Ag(s) + H 2 O (Aldehyde) (Tollens’ reagent) (Carboxylic acid) (Elemental Silver) What is Tollens’ Reagent?

Which is the correct formula for Fehling’s reagent?

This compound doesn’t reduce Tollens’ or Fehlings’ reagent, and it does not decolourize bromine water or Baeyer’s reagent. On excessive oxidation with chromic acid, it gives a carboxylic acid (B) having molecular formula C 7 H 6 O 2. Determine the compounds (A) and (B) and explain the reactions involved.

How is Tollens reagent used in glucose differentiation?

Therefore tollens’ reagent is used in the identification and differentiation of carbohydrates/sugars on the basis of their ability to reduce Tollens’ reagent/ Benedict’s solution or Fehling’s solution. Example: Glucose is a reducing sugar as it has a free aldehyde group.

What do you need to know about Fehling’s solution?

What is Fehling’s Solution? Fehling’s solution is a deep blue alkaline solution which is used to identify the presence of aldehydes or groups that contain any aldehyde functional group -CHO and in addition with Tollen’s reagent to differentiate between reducing and non-reducing sugars.