Match List-I with List-II. List-I Element detected List-II Reagent used/Product formed A Nitrogen I Na 2 Fe CN 5 NO B Sulphur II AgNO 3 C Phosphorus III Fe 4 Fe CN 6 3 D Halogen IV NH 4 2 MoO 4 Choose the correct answer from the options given below:

A → III ; B → I ; C → IV ; D → II

A → II ; B → IV ; C → I ; D → III

A → IV ; B → II ; C → I ; D → III

A → II ; B → I ; C → IV ; D → III

Match List-I with List-II List-I List-II Test/Reagents/Observation(s) Species detected (a) Lassaigne's Test (i) Carbon (b) Cu(II) oxide (ii) Sulphur (c) Silver nitrate (iii) N , S , P , and halogen (d) The sodium fusion extract gives black precipitate with acetic acid and lead acetate (iv) Halogen Specifically The correct match is :

( a ) - ( iii ) , ( b ) - ( i ) , ( c ) - ( iv ) , ( d ) - ( ii )

( a ) - ( iii ) , ( b ) - ( i ) , ( c ) - ( ii ) , ( d ) - ( iv )

( a ) - ( i ) , ( b ) - ( iv ) , ( c ) - ( iii ) , ( d ) - ( ii )

( a ) - ( i ) , ( b ) - ( ii ) , ( c ) - ( iv ) , ( d ) - ( iii )

EASY

Earn 100

In Lassaigne's solution, pink/violet colouration is produced when sodium nitroprusside solution is added. It indicates the presence of

50% studentsanswered this correctly

Important Questions on Organic Chemistry- Some Basic Principles and Techniques

EASY

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

The formula of the purple colour formed in Lassaigne's test for sulphur using sodium nitroprusside is

EASY

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

In Lassaigne's test for halogens, it is necessary to remove

' X'

and

' Y'

from the sodium fusion extract, if nitrogen and Sulphur are present. This is done by boiling the extract with

' Z'

. Identify

X, Y

and

Z

MEDIUM

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

Given below are two statements :

Statement I : In 'Lassaigne's Test', when both nitrogen and sulphur are present in an organic compound, sodium thiocyanate is formed.

Statement II : If both nitrogen and sulphur are present in an organic compound, then the excess of sodium used in sodium fusion will decompose the sodium thiocyanate formed to give $NaCN$ and ${Na}_{2} S$ .

In the light of the above statements, choose the most appropriate answer from the options given below

EASY

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

A solution of ${FeCl}_{3}$ when treated with $K_{4} [Fe (CN)_{6}]$ gives a prussian blue precipitate due to the formation of

MEDIUM

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

During the fusion of organic compound with sodium metal, nitrogen present in the organic compound is converted into

MEDIUM

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

Given below are two statements:

Statement I: Sulphanilic acid gives esterification test for carboxyl group.

Statement II: Sulphanilic acid gives red colour in Lassigne’s test for extra element detection.

In the light of the above statements, choose the most appropriate answer from the options given below:

EASY

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

The blood red color of sulfur containing organic compound of Lassaigne's extract is due to the formation of ________

MEDIUM

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

Which of the following compound is added to the sodium extract before addition of silver nitrate for testing of halogens?

EASY

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

In Lassaigne's test, on boiling sodium thiocyanate with ferrous sulphate produces

EASY

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

The potassium ferrocyanide solution gives a Prussian blue colour, when added to :

MEDIUM

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

Match List-I with List-II.

List-I Element detected		List-II Reagent used/Product formed
$A$	Nitrogen	$I$	${Na}_{2} [Fe {(CN)}_{5} NO]$
$B$	Sulphur	$II$	${AgNO}_{3}$
$C$	Phosphorus	$III$	${Fe}_{4} {[Fe {(CN)}_{6}]}_{3}$
$D$	Halogen	$IV$	${({NH}_{4})}_{2} {MoO}_{4}$

Choose the correct answer from the options given below:

MEDIUM

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

When nitrogen and chlorine containing organic compound is reacted with sodium metal, it forms

EASY

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

Sodium extract is heated with concentrated

H N O_{3}

before testing for halogens because :

MEDIUM

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

Compound that will give positive Lassaigne's test for both nitrogen and halogen is

EASY

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

Which of the following compound will give blood red colour while doing the Lassaigne's test for

N

HARD

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

Match List-I with List-II

	List-I		List-II
	Test/Reagents/Observation(s)		Species detected
(a)	Lassaigne's Test	(i)	Carbon
(b)	Cu(II) oxide	(ii)	Sulphur
(c)	Silver nitrate	(iii)	$N, S, P$ , and halogen
(d)	The sodium fusion extract gives black precipitate with acetic acid and lead acetate	(iv)	Halogen Specifically

The correct match is :

EASY

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

Reagent,

1 -

naphthylamine and sulphanilic acid in acetic acid is used for the detection of

EASY

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

An iodo-organic compound, when fused with sodium metal, followed by acidification with nitric acid and then treated with silver nitrate gives

MEDIUM

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

In the detection of nitrogen of an organic compound by Lassaigne's test, a prussian blue colour is obtained. This is due to the formation of which of the following complexes?

HARD

Chemistry>Organic Chemistry>Organic Chemistry- Some Basic Principles and Techniques>Qualitative Analysis of Organic Compounds

Match the organic compounds in column -

I

with the Lassaigne's test result in column -

II

appropriately:

	Column – $I$		Column - $II$
A.	Aniline	i.	Red colour with $F e C l_{3}$
B.	Benzene sulfonic acid	ii.	Violet color with sodium nitroprusside
C.	Thiourea	iii.	Blue color with and acidic solution of $F e S O_{4}$

In Lassaigne's solution, pink/violet colouration is produced when sodium nitroprusside solution is added. It indicates the presence of

Important Questions on Organic Chemistry- Some Basic Principles and Techniques

Learn and Prepare for any exam you want !