Class 11Chemistry8-3.Organic Chemistry : Purification and characterizationChemical analysis of organic compounds
MediumGive the answers for the Lassaigne test:
$(i)$ If nitrogen and sulphur are both present,what observation is observed?
$(ii)$ If bromine is present,what is the observation?
$(iii)$ In the Lassaigne extract,if black precipitates are not obtained upon adding $CH_3COOH$ and lead acetate,what does this indicate?
$(iv)$ What is the reason for adding $FeSO_4$ to the Lassaigne extract?
$(v)$ Why is the Prussian blue colour observed?
$(vi)$ What does the violet colour with sodium nitroprusside in the Lassaigne extract indicate?
$(i)$ If nitrogen and sulphur are both present,what observation is observed?
$(ii)$ If bromine is present,what is the observation?
$(iii)$ In the Lassaigne extract,if black precipitates are not obtained upon adding $CH_3COOH$ and lead acetate,what does this indicate?
$(iv)$ What is the reason for adding $FeSO_4$ to the Lassaigne extract?
$(v)$ Why is the Prussian blue colour observed?
$(vi)$ What does the violet colour with sodium nitroprusside in the Lassaigne extract indicate?
(N/A) $(i)$ $A$ blood-red colour is obtained due to the formation of $[Fe(SCN)]^{2+}$.
$(ii)$ By adding $AgNO_3$,a pale yellow precipitate of $AgBr$ is formed.
$(iii)$ It indicates that sulphur is absent in the organic compound.
$(iv)$ $FeSO_4$ is added to react with $CN^-$ ions to form ferrocyanide ions,which then react with $Fe^{3+}$ ions.
$(v)$ It is due to the formation of ferric ferrocyanide,$Fe_4[Fe(CN)_6]_3$.
$(vi)$ It indicates that sulphur is present in the compound,forming $Na_4[Fe(CN)_5NOS]$.
$(ii)$ By adding $AgNO_3$,a pale yellow precipitate of $AgBr$ is formed.
$(iii)$ It indicates that sulphur is absent in the organic compound.
$(iv)$ $FeSO_4$ is added to react with $CN^-$ ions to form ferrocyanide ions,which then react with $Fe^{3+}$ ions.
$(v)$ It is due to the formation of ferric ferrocyanide,$Fe_4[Fe(CN)_6]_3$.
$(vi)$ It indicates that sulphur is present in the compound,forming $Na_4[Fe(CN)_5NOS]$.
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Similar Questions
Appearance of blood red colour,on treatment of the sodium fusion extract of an organic compound with $FeSO_4$ in presence of concentrated $H_2SO_4$ indicates the presence of element/s
DifficultJEE MAIN 2024
View SolutionWhat is the fundamental principle of the Lassaigne test?
Easy
View SolutionMatch List-$I$ with List-$II$:
List-$I$ (Test/Reagents/Observation) List-$II$ (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:
| List-$I$ (Test/Reagents/Observation) | List-$II$ (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:
During the detection of phosphorus in an organic compound,a yellow precipitate is formed due to the formation of:
Easy
View SolutionWhich one of the following sets of elements can be detected using sodium fusion extract?
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