NEET  >  Additional Documents & Tests for NEET  >  Theory & Procedure, Qualitative Analysis of Carbohydrates

Theory & Procedure, Qualitative Analysis of Carbohydrates Notes | Study Additional Documents & Tests for NEET - NEET

Document Description: Theory & Procedure, Qualitative Analysis of Carbohydrates for NEET 2022 is part of Additional Documents & Tests for NEET preparation. The notes and questions for Theory & Procedure, Qualitative Analysis of Carbohydrates have been prepared according to the NEET exam syllabus. Information about Theory & Procedure, Qualitative Analysis of Carbohydrates covers topics like and Theory & Procedure, Qualitative Analysis of Carbohydrates Example, for NEET 2022 Exam. Find important definitions, questions, notes, meanings, examples, exercises and tests below for Theory & Procedure, Qualitative Analysis of Carbohydrates.

Introduction of Theory & Procedure, Qualitative Analysis of Carbohydrates in English is available as part of our Additional Documents & Tests for NEET for NEET & Theory & Procedure, Qualitative Analysis of Carbohydrates in Hindi for Additional Documents & Tests for NEET course. Download more important topics related with notes, lectures and mock test series for NEET Exam by signing up for free. NEET: Theory & Procedure, Qualitative Analysis of Carbohydrates Notes | Study Additional Documents & Tests for NEET - NEET
1 Crore+ students have signed up on EduRev. Have you?

Our objective

Our objective is to study some simple tests of carbohydrates.

The Theory

What are Carbohydrates?

Carbohydrates are most abundant organic compounds found in living organisms and are composed of carbon, hydrogen and oxygen. Carbohydrates act as the primary source to provide energy for functioning of living organisms. These are called carbohydrates because they can be considered as hydrates of carbon. Most of them have the general formula Cx(H2O)y.

Theory & Procedure, Qualitative Analysis of Carbohydrates Notes | Study Additional Documents & Tests for NEET - NEET

Generally carbohydrates are defined as polyhydroxy aldehydes or polyhydroxy ketones or the compounds which produces such products on hydrolysis. Carbohydrates are called saccharides. Some of them have sweet taste and are called sugars.

How do you classify carbohydrates based on reactivity?

Based on the reactivity with Tollen’s, Benedict’s or Fehling’s reagent, carbohydrates are classified as;

Reducing sugars

Carbohydrates that can reduce Tollen’s, Benedict’s or Fehling’s reagents are called reducing sugars (sugar with free aldehyde or ketone group). All monosaccharides and most of the disaccharides are reducing sugars. Some examples are Maltose and Lactose.

Non-reducing sugars

Carbohydrates that cannot reduce Tollen’s, Benedict’s or Fehling’s reagents are called non-reducing sugars. Sucrose is a non-reducing sugar.

Some Important Tests for the Detection of Carbohydrates

Molisch’s test

Molisch’s reagent is 10% alcoholic solution of α-naphthol. This is a common chemical test to detect the presence of carbohydrates. Carbohydrates undergo dehydration by sulphuric acid to form furfural (furfuraldehyde) that reacts with α-naphthol to form a violet coloured product.

Fehling's test

This is an important test to detect the presence of reducing sugars. Fehling’s solution A is copper sulphate solution and Fehling’s solution B is potassium sodium tartrate. On heating, carbohydrate reduces deep blue solution of copper (II) ions to red precipitate of insoluble copper oxide.

«math xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mtable»«mtr»«mtd»«munder»«mi mathvariant=¨normal¨»C«/mi»«mi mathvariant=¨normal¨»I«/mi»«/munder»«mi mathvariant=¨normal¨»H«/mi»«mi mathvariant=¨normal¨»O«/mi»«mo»§nbsp;«/mo»«mo»§nbsp;«/mo»«/mtd»«/mtr»«mtr»«mtd»«munder»«mrow»«mo»(«/mo»«mi mathvariant=¨normal¨»C«/mi»«/mrow»«mrow»«mo»§nbsp;«/mo»«mi mathvariant=¨normal¨»I«/mi»«/mrow»«/munder»«mi mathvariant=¨normal¨»H«/mi»«mi mathvariant=¨normal¨»O«/mi»«mi mathvariant=¨normal¨»H«/mi»«msub»«mo»)«/mo»«mn»4«/mn»«/msub»«/mtd»«/mtr»«mtr»«mtd»«munder»«mrow»«mi mathvariant=¨normal¨»C«/mi»«msub»«mi mathvariant=¨normal¨»H«/mi»«mn»2«/mn»«/msub»«mi mathvariant=¨normal¨»O«/mi»«mi mathvariant=¨normal¨»H«/mi»«/mrow»«mrow»«mi mathvariant=¨normal¨»G«/mi»«mi mathvariant=¨normal¨»l«/mi»«mi mathvariant=¨normal¨»u«/mi»«mi mathvariant=¨normal¨»cos«/mi»«mi mathvariant=¨normal¨»e«/mi»«/mrow»«/munder»«/mtd»«/mtr»«/mtable»«mo»§nbsp;«/mo»«mo»+«/mo»«mo»§nbsp;«/mo»«mn»2«/mn»«mi mathvariant=¨normal¨»Cu«/mi»«mo»(«/mo»«mi mathvariant=¨normal¨»OH«/mi»«msub»«mo»)«/mo»«mn»2«/mn»«/msub»«mo»§nbsp;«/mo»«mo»+«/mo»«mo»§nbsp;«/mo»«mi mathvariant=¨normal¨»NaOH«/mi»«mo»§nbsp;«/mo»«munderover»«mo»§#8594;«/mo»«mrow»«mi mathvariant=¨normal¨»i«/mi»«mi mathvariant=¨normal¨»o«/mi»«mi mathvariant=¨normal¨»n«/mi»«mi mathvariant=¨normal¨»s«/mi»«/mrow»«mrow»«mi mathvariant=¨normal¨»T«/mi»«mi mathvariant=¨normal¨»a«/mi»«mi mathvariant=¨normal¨»r«/mi»«mi mathvariant=¨normal¨»t«/mi»«mi mathvariant=¨normal¨»r«/mi»«mi mathvariant=¨normal¨»a«/mi»«mi mathvariant=¨normal¨»t«/mi»«mi mathvariant=¨normal¨»e«/mi»«/mrow»«/munderover»«mo»§nbsp;«/mo»«mtable»«mtr»«mtd»«munder»«mi mathvariant=¨normal¨»C«/mi»«mi mathvariant=¨normal¨»I«/mi»«/munder»«mi mathvariant=¨normal¨»O«/mi»«msup»«mi mathvariant=¨normal¨»O«/mi»«mo»-«/mo»«/msup»«mi mathvariant=¨normal¨»N«/mi»«msup»«mi mathvariant=¨normal¨»a«/mi»«mo»+«/mo»«/msup»«/mtd»«/mtr»«mtr»«mtd»«munder»«mrow»«mo»(«/mo»«mi mathvariant=¨normal¨»C«/mi»«/mrow»«mrow»«mo»§nbsp;«/mo»«mi mathvariant=¨normal¨»I«/mi»«/mrow»«/munder»«mi mathvariant=¨normal¨»H«/mi»«mi mathvariant=¨normal¨»O«/mi»«mi mathvariant=¨normal¨»H«/mi»«msub»«mo»)«/mo»«mn»4«/mn»«/msub»«mo»§nbsp;«/mo»«mo»§nbsp;«/mo»«mo»§nbsp;«/mo»«mo»§nbsp;«/mo»«/mtd»«/mtr»«mtr»«mtd»«munder»«mrow»«mi mathvariant=¨normal¨»C«/mi»«msub»«mi mathvariant=¨normal¨»H«/mi»«mn»2«/mn»«/msub»«mi mathvariant=¨normal¨»O«/mi»«mi mathvariant=¨normal¨»H«/mi»«/mrow»«mrow»«mi mathvariant=¨normal¨»S«/mi»«mi mathvariant=¨normal¨»o«/mi»«mi mathvariant=¨normal¨»d«/mi»«mo».«/mo»«mo»§nbsp;«/mo»«mi mathvariant=¨normal¨»S«/mi»«mi mathvariant=¨normal¨»a«/mi»«mi mathvariant=¨normal¨»l«/mi»«mi mathvariant=¨normal¨»t«/mi»«mo»§nbsp;«/mo»«mi mathvariant=¨normal¨»o«/mi»«mi mathvariant=¨normal¨»f«/mi»«mo»§nbsp;«/mo»«mi mathvariant=¨normal¨»g«/mi»«mi mathvariant=¨normal¨»l«/mi»«mi mathvariant=¨normal¨»u«/mi»«mi mathvariant=¨normal¨»c«/mi»«mi mathvariant=¨normal¨»o«/mi»«mi mathvariant=¨normal¨»n«/mi»«mi mathvariant=¨normal¨»u«/mi»«mi mathvariant=¨normal¨»c«/mi»«mo»§nbsp;«/mo»«mi mathvariant=¨normal¨»a«/mi»«mi mathvariant=¨normal¨»c«/mi»«mi mathvariant=¨normal¨»i«/mi»«mi mathvariant=¨normal¨»d«/mi»«/mrow»«/munder»«mo»§nbsp;«/mo»«mo»§nbsp;«/mo»«mo»§nbsp;«/mo»«mo»§nbsp;«/mo»«mo»§nbsp;«/mo»«/mtd»«/mtr»«/mtable»«mo»+«/mo»«mo»§nbsp;«/mo»«mn»3«/mn»«msub»«mi mathvariant=¨normal¨»H«/mi»«mn»2«/mn»«/msub»«mi mathvariant=¨normal¨»O«/mi»«mo»§nbsp;«/mo»«mo»+«/mo»«munder»«mrow»«mi mathvariant=¨normal¨»C«/mi»«msub»«mi mathvariant=¨normal¨»u«/mi»«mn»2«/mn»«/msub»«mi mathvariant=¨normal¨»O«/mi»«/mrow»«mrow»«mi mathvariant=¨normal¨»R«/mi»«mi mathvariant=¨normal¨»e«/mi»«mi mathvariant=¨normal¨»d«/mi»«mo»§nbsp;«/mo»«mi mathvariant=¨normal¨»p«/mi»«mi mathvariant=¨normal¨»p«/mi»«mi mathvariant=¨normal¨»t«/mi»«mo».«/mo»«/mrow»«/munder»«/math»

Benedict's test

Benedict’s test distinguishes reducing sugar from non-reducing sugar. Benedict’s reagent contains blue copper (II) ions (Cu2+, cupric ions) that are reduced to copper (I) ions (Cu+, cuprous ions) by carbohydrates. These ions form precipitate as red coloured cuprous (copper (I) oxide. 

«math xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mtable columnalign=¨left¨ rowspacing=¨0¨»«mtr»«mtd»«msub»«mi mathvariant=¨normal¨»CuSO«/mi»«mn»4«/mn»«/msub»«mo»§nbsp;«/mo»«mo»§#8594;«/mo»«mo»§nbsp;«/mo»«msup»«mi mathvariant=¨normal¨»Cu«/mi»«mrow»«mn»2«/mn»«mo»+«/mo»«/mrow»«/msup»«mo»§nbsp;«/mo»«mo»+«/mo»«mo»§nbsp;«/mo»«msup»«msub»«mi mathvariant=¨normal¨»SO«/mi»«mn»4«/mn»«/msub»«mrow»«mn»2«/mn»«mo»-«/mo»«/mrow»«/msup»«/mtd»«/mtr»«mtr»«mtd/»«/mtr»«mtr»«mtd»«msup»«mi mathvariant=¨normal¨»Cu«/mi»«mrow»«mn»2«/mn»«mo»+«/mo»«/mrow»«/msup»«mo»§nbsp;«/mo»«mo»+«/mo»«mo»§nbsp;«/mo»«mi mathvariant=¨normal¨»Reducing«/mi»«mo»§nbsp;«/mo»«mi mathvariant=¨normal¨»sugar«/mi»«mo»§nbsp;«/mo»«mo»§#8594;«/mo»«mo»§nbsp;«/mo»«msup»«mi mathvariant=¨normal¨»Cu«/mi»«mo»+«/mo»«/msup»«/mtd»«/mtr»«mtr»«mtd/»«/mtr»«mtr»«mtd»«msup»«mi mathvariant=¨normal¨»Cu«/mi»«mo»+«/mo»«/msup»«mo»§nbsp;«/mo»«mo»§#8594;«/mo»«mo»§nbsp;«/mo»«msub»«mi mathvariant=¨normal¨»Cu«/mi»«msup»«mrow/»«mn»2«/mn»«/msup»«/msub»«mi mathvariant=¨normal¨»O«/mi»«/mtd»«/mtr»«/mtable»«/math»

Tollen’s test

Tollen’s reagent is ammoniacal silver nitrate solution. On reacting with carbohydrate elemental silver is precipitating out of the solution, occasionally onto the inner surface of the reaction vessel. This produces silver mirror on the inner wall of the reaction vessel.

 «math xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mtable columnalign=¨left¨ rowspacing=¨0¨»«mtr»«mtd»«msub»«mi mathvariant=¨normal¨»AgNO«/mi»«mn»3«/mn»«/msub»«mo»§nbsp;«/mo»«mo»+«/mo»«mo»§nbsp;«/mo»«msub»«mi mathvariant=¨normal¨»NH«/mi»«mn»4«/mn»«/msub»«mi mathvariant=¨normal¨»OH«/mi»«mo»§nbsp;«/mo»«mo»§#8594;«/mo»«mo»§nbsp;«/mo»«msub»«mi mathvariant=¨normal¨»NH«/mi»«mn»4«/mn»«/msub»«msub»«mi mathvariant=¨normal¨»NO«/mi»«mn»3«/mn»«/msub»«mo»§nbsp;«/mo»«mo»+«/mo»«mo»§nbsp;«/mo»«mi mathvariant=¨normal¨»AgOH«/mi»«/mtd»«/mtr»«mtr»«mtd/»«/mtr»«mtr»«mtd»«mn»2«/mn»«mi mathvariant=¨normal¨»AgOH«/mi»«mo»§nbsp;«/mo»«mo»§#8594;«/mo»«mo»§nbsp;«/mo»«msub»«mi mathvariant=¨normal¨»Ag«/mi»«mn»2«/mn»«/msub»«mi mathvariant=¨normal¨»O«/mi»«mo»§nbsp;«/mo»«mo»+«/mo»«mo»§nbsp;«/mo»«msub»«mi mathvariant=¨normal¨»H«/mi»«mn»2«/mn»«/msub»«mi mathvariant=¨normal¨»O«/mi»«/mtd»«/mtr»«mtr»«mtd/»«/mtr»«mtr»«mtd»«msub»«mi mathvariant=¨normal¨»Ag«/mi»«mn»2«/mn»«/msub»«mi mathvariant=¨normal¨»O«/mi»«mo»§nbsp;«/mo»«mo»+«/mo»«mo»§nbsp;«/mo»«mn»2«/mn»«msub»«mi mathvariant=¨normal¨»NH«/mi»«mn»4«/mn»«/msub»«mi mathvariant=¨normal¨»OH«/mi»«mo»§nbsp;«/mo»«mo»§#8594;«/mo»«mo»§nbsp;«/mo»«mn»2«/mn»«mo»[«/mo»«mi mathvariant=¨normal¨»Ag«/mi»«munder»«mrow»«mo»(«/mo»«msub»«mi mathvariant=¨normal¨»NH«/mi»«mn»3«/mn»«/msub»«msub»«mo»)«/mo»«mn»2«/mn»«/msub»«/mrow»«mrow»«mo»(«/mo»«mi mathvariant=¨normal¨»S«/mi»«mi mathvariant=¨normal¨»o«/mi»«mi mathvariant=¨normal¨»l«/mi»«mi mathvariant=¨normal¨»u«/mi»«mi mathvariant=¨normal¨»b«/mi»«mi mathvariant=¨normal¨»l«/mi»«mi mathvariant=¨normal¨»e«/mi»«mo»)«/mo»«/mrow»«/munder»«mo»]«/mo»«mi mathvariant=¨normal¨»OH«/mi»«mo»§nbsp;«/mo»«mo»+«/mo»«mo»§nbsp;«/mo»«mn»3«/mn»«msub»«mi mathvariant=¨normal¨»H«/mi»«mn»2«/mn»«/msub»«mi mathvariant=¨normal¨»O«/mi»«/mtd»«/mtr»«mtr»«mtd/»«/mtr»«mtr»«mtd»«mtable»«mtr»«mtd»«munder»«mi mathvariant=¨normal¨»C«/mi»«mi mathvariant=¨normal¨»I«/mi»«/munder»«msub»«mi mathvariant=¨normal¨»H«/mi»«mn»2«/mn»«/msub»«mi mathvariant=¨normal¨»OH«/mi»«/mtd»«/mtr»«mtr»«mtd»«mo»(«/mo»«mi mathvariant=¨normal¨»C«/mi»«mi mathvariant=¨normal¨»H«/mi»«mi mathvariant=¨normal¨»O«/mi»«mi mathvariant=¨normal¨»H«/mi»«msub»«mo»)«/mo»«mn»4«/mn»«/msub»«mo»§nbsp;«/mo»«/mtd»«/mtr»«mtr»«mtd»«munder»«mrow»«mover»«mi mathvariant=¨normal¨»C«/mi»«mi mathvariant=¨normal¨»I«/mi»«/mover»«mi mathvariant=¨normal¨»H«/mi»«mi mathvariant=¨normal¨»O«/mi»«mo»§nbsp;«/mo»«mo»§nbsp;«/mo»«mo»§nbsp;«/mo»«/mrow»«mrow»«mo»(«/mo»«mi mathvariant=¨normal¨»G«/mi»«mi mathvariant=¨normal¨»l«/mi»«mi mathvariant=¨normal¨»u«/mi»«mi mathvariant=¨normal¨»cos«/mi»«mi mathvariant=¨normal¨»e«/mi»«mo»)«/mo»«mo»§nbsp;«/mo»«mo»§nbsp;«/mo»«/mrow»«/munder»«/mtd»«/mtr»«/mtable»«mo»§nbsp;«/mo»«mo»+«/mo»«mo»§nbsp;«/mo»«msub»«mi mathvariant=¨normal¨»Ag«/mi»«mn»2«/mn»«/msub»«mi mathvariant=¨normal¨»O«/mi»«mo»§nbsp;«/mo»«mover»«mo»§#8594;«/mo»«mrow»«msub»«mi mathvariant=¨normal¨»NH«/mi»«mn»4«/mn»«/msub»«mi mathvariant=¨normal¨»OH«/mi»«/mrow»«/mover»«mo»§nbsp;«/mo»«mtable»«mtr»«mtd»«munder»«mi mathvariant=¨normal¨»C«/mi»«mi mathvariant=¨normal¨»I«/mi»«/munder»«mi mathvariant=¨normal¨»O«/mi»«mi mathvariant=¨normal¨»O«/mi»«mi mathvariant=¨normal¨»H«/mi»«/mtd»«/mtr»«mtr»«mtd»«mo»(«/mo»«mi mathvariant=¨normal¨»C«/mi»«mi mathvariant=¨normal¨»H«/mi»«mi mathvariant=¨normal¨»O«/mi»«mi mathvariant=¨normal¨»H«/mi»«msub»«mo»)«/mo»«mn»4«/mn»«/msub»«/mtd»«/mtr»«mtr»«mtd»«munder»«mrow»«mover»«mi mathvariant=¨normal¨»C«/mi»«mi mathvariant=¨normal¨»I«/mi»«/mover»«mi mathvariant=¨normal¨»O«/mi»«mi mathvariant=¨normal¨»O«/mi»«mi mathvariant=¨normal¨»H«/mi»«/mrow»«mrow»«mo»(«/mo»«mi mathvariant=¨normal¨»G«/mi»«mi mathvariant=¨normal¨»l«/mi»«mi mathvariant=¨normal¨»u«/mi»«mi mathvariant=¨normal¨»c«/mi»«mi mathvariant=¨normal¨»o«/mi»«mi mathvariant=¨normal¨»n«/mi»«mi mathvariant=¨normal¨»i«/mi»«mi mathvariant=¨normal¨»c«/mi»«mo»§nbsp;«/mo»«mi mathvariant=¨normal¨»a«/mi»«mi mathvariant=¨normal¨»c«/mi»«mi mathvariant=¨normal¨»i«/mi»«mi mathvariant=¨normal¨»d«/mi»«mo»)«/mo»«/mrow»«/munder»«/mtd»«/mtr»«/mtable»«mo»§nbsp;«/mo»«mo»+«/mo»«mo»§nbsp;«/mo»«munder»«mrow»«mn»2«/mn»«mi mathvariant=¨normal¨»A«/mi»«mi mathvariant=¨normal¨»g«/mi»«/mrow»«mrow»«mo»(«/mo»«mi mathvariant=¨normal¨»S«/mi»«mi mathvariant=¨normal¨»i«/mi»«mi mathvariant=¨normal¨»l«/mi»«mi mathvariant=¨normal¨»v«/mi»«mi mathvariant=¨normal¨»e«/mi»«mi mathvariant=¨normal¨»r«/mi»«mo»§nbsp;«/mo»«mi mathvariant=¨normal¨»m«/mi»«mi mathvariant=¨normal¨»i«/mi»«mi mathvariant=¨normal¨»r«/mi»«mi mathvariant=¨normal¨»r«/mi»«mi mathvariant=¨normal¨»o«/mi»«mi mathvariant=¨normal¨»r«/mi»«mo»)«/mo»«/mrow»«/munder»«/mtd»«/mtr»«/mtable»«/math»

Iodine test

Iodine test is used to detect the presence of starch. Iodine is not much soluble in water so iodine solution is prepared by dissolving iodine in water in presence of potassium iodide. Iodine dissolved in an aqueous solution of potassium iodide reacts with starch to form a starch/iodine complex which gives characteristics blue black colour to the reaction mixture.

Theory & Procedure, Qualitative Analysis of Carbohydrates Notes | Study Additional Documents & Tests for NEET - NEET

Learning Outcomes

  • Students understand various identification tests for carbohydrates.
  • Students acquire the skill to distinguish reducing and non-reducing sugars.
  • Students acquire skill to perform the experiment in the real lab.

Materials Required

Samples

  • Glucose
  • Sucrose
  • Starch

Reagents

  • Distilled water
  • Molisch’s reagent
  • Fehling’s solution A
  • Fehling’s solution B
  • Benedict’s reagent
  • Tollen’s reagent
  • Iodine solution

Apparatus

  • Test tube
  • Dropper
  • Beaker

Procedure

Real Lab Procedure

Solubility test

Take a small amount of the given sample in a test tube and add 3 ml of distilled water into it and shake the test tube well.

Observation

SI No.
 Sample
 Observation
1.
 Glucose
 Soluble
2.
 Sucrose
 Soluble
3.
 Starch
 Insoluble


Inference

Glucose and sucrose are soluble in water whereas starch is insoluble in water.

Molisch’s test

Take about 2 ml of aqueous solution of the sample in a test tube and add few drops of Molisch’s reagent into it. Pour 1 ml conc. H2SO4 slowly along the side of the test tube.

Observation

SI No.
 Sample
 Observation
1.
 Glucose
 A red violet (purple) ring is formed at the junction of two layers.
2.
 Sucrose
 A red violet (purple) ring is formed at the junction of two layers.
3.
 Starch
 A red violet (purple) ring is formed at the junction of the two layers.


Inference

Presence of carbohydrate is confirmed.

Fehling’s test

Take 2 ml of aqueous solution of the sample in a test tube and add 1-2 ml each of Fehling’s solution A and Fehling’s solution B into it. Keep the test tube in a boiling water bath.

Observation

SI No.
 Sample
 Observation
1.
 Glucose
 A reddish precipitate is formed.
2.
 Sucrose
 No formation of reddish precipitate.
3.
 Starch
 No formation of reddish precipitate.


Inference

Reddish precipitate indicates the presence of a reducing sugar.

Benedict’s test

Take 1-2 ml of aqueous solution of the sample in a test tube and add 1-2 ml of Benedict’s reagent. Keep the test tube in a boiling water bath.

Observation

SI No.
 Sample
 Observation
1.
 Glucose
 A reddish precipitate is formed.
2.
 Sucrose
 No formation of reddish precipitate.
3.
 Starch
 No formation of reddish precipitate.


 Inference

Reddish precipitate indicates the presence of a reducing sugar.

Tollen’s test

Take 2-3 ml of aqueous solution of the sample in a test tube and add 2-3 ml of Tollen’s reagent. Keep the test tube in a boiling water bath for 10 minutes.

Observation

SI No.
 Sample
 Observation
1.
 Glucose
 A shinning silver mirror is formed.
2.
 Sucrose
 No formation of silver mirror.
3.
 Starch
 No formation of silver mirror.


Inference

A shinning silver mirror indicates the presence of a reducing sugar.

Iodine test

Take a small amount of aqueous solution of the sample in a test tube and add 1-2 drops of iodine solution into it.

Observation

SI No.
 Sample
 Observation
1.
 Glucose
 No characteristic change.
2.
 Sucrose
 No characteristic change.
3.
 Starch
 A blue colour is formed.


Inference

Appearance of blue colouration indicates the presence of starch.

Simulator Procedure (as performed through the Online Labs)

You can select the test from ‘Select the test’ drop down list.

Solubility Test

  • Drag the dropper towards the test tubes to drop water into test tubes A, B, C and D respectively.
  • Drag the test tubes A, B, C and D respectively to shake the test tubes well.
  • Click on the inference icon to see the inference.

Molisch’s Test

  • Drag the dropper towards the test tubes to drop Molisch’s reagent into test tubes A, B, C and D respectively.
  • Drag test tube A towards the reagent bottles to place it in a slanting position.
  • Drag the dropper towards test tube A to drop Conc. H2SO4 slowly along the side of the test tube.
  • Drag the test tube B towards the reagent bottles to place it in a slanting position.
  • Drag the dropper towards test tube B to drop Conc. H2SO4 slowly along the side of the test tube.
  • Drag the test tube C towards the reagent bottles to place it in a slanting position.
  • Drag the dropper towards test tube C to drop Conc. H2SO4 slowly along the side of the test tube.
  • Drag test tube D towards the reagent bottles to place it in a slanting position.
  • Drag the dropper towards test tube D to drop Conc. H2SO4 slowly along the side of the test tube.
  • Click on the inference icon to see the inference.

Fehling’s Test

  • Drag the dropper towards the test tubes to drop Fehling’s solution A into test tubes A, B, C and D respectively.
  • Drag the dropper towards the test tubes to drop Fehling’s solution B into test tubes A, B, C and D respectively.
  • To place the test tubes in a water bath, click on the button ‘Place the test tubes in water bath’.
  • Click on the inference icon to see the inference.

Benedict’s Test

  • Drag the dropper towards the test tubes to drop Benedict’s reagent into the test tubes A, B, C and D respectively.
  • To place the test tubes in water bath, click on the button ‘Place the test tubes in water bath’
  • Click on the inference icon to see the inference.

Tollen’s Test

  • Drag the dropper towards the test tubes to drop Tollen’s reagent into test tubes A, B, C and D respectively.
  • Click on the ‘Next’ button to go to the next step.
  • To place the test tubes in water bath, click on the button ‘Place the test tubes in water bath’
  • Click on the inference icon to see the inference.

Iodine Test

  • Drag the dropper towards the test tubes to drop iodine solution into test tubes A, B, C and D respectively.
  • Click on the inference icon to see the inference.

To redo the experiment, click on the ‘Reset’ button.

Note: Click on the ‘HELP’ button to see the instructions.

Precautions

  • Handle the chemicals with care.
  • Heating should be done very carefully.
  • Use droppers to take reagents from the bottles.
The document Theory & Procedure, Qualitative Analysis of Carbohydrates Notes | Study Additional Documents & Tests for NEET - NEET is a part of the NEET Course Additional Documents & Tests for NEET.
All you need of NEET at this link: NEET
Download as PDF

How to Prepare for NEET

Read our guide to prepare for NEET which is created by Toppers & the best Teachers

Download free EduRev App

Track your progress, build streaks, highlight & save important lessons and more!

Related Searches

Qualitative Analysis of Carbohydrates Notes | Study Additional Documents & Tests for NEET - NEET

,

Theory & Procedure

,

Important questions

,

Free

,

Qualitative Analysis of Carbohydrates Notes | Study Additional Documents & Tests for NEET - NEET

,

Previous Year Questions with Solutions

,

pdf

,

MCQs

,

Sample Paper

,

past year papers

,

shortcuts and tricks

,

Summary

,

Objective type Questions

,

practice quizzes

,

video lectures

,

Qualitative Analysis of Carbohydrates Notes | Study Additional Documents & Tests for NEET - NEET

,

ppt

,

Theory & Procedure

,

Semester Notes

,

Theory & Procedure

,

Extra Questions

,

Viva Questions

,

study material

,

Exam

,

mock tests for examination

;