Download App

STD 11 - 8.3. Organic chemistry purification and characterization — JEE STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceJEESTD 11 - 8.3. Organic chemistry purification and characterization4 Marks
MCQ
If $N$ and $S$ are present in an organic compound during Lassaigne test, then both changes into
  • A
    $N{a_2}S$ and $NaCN$
  • ✓
    $NaSCN$
  • C
    $N{a_2}S{O_3}$ and $NaCN$
  • D
    $N{a_2}S$ and $NaCNO$
✓

Answer

Correct option: B.
$NaSCN$
b
(b) When sulphur and nitrogen both are present in organic compound during Lassaigne's Test, both changes into "sodium thiocyanate". $(NaSCN)$ which gives a blood red colouration with Ferric ion.

$3NaCNS + FeC{l_3} \to \mathop {\mathop {Fe{{(CNS)}_3}}\limits_{{\rm{Ferric sulpho cyanide}}} }\limits_{{\rm{(Blood red colour)}}} + 3NaCl$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

JEE STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

In which of the following species the bonds are non-directional?
→
The bonds in ${K_4}\,[Fe\,{(CN)_6}]$ are
→
Select Paramagnetic molecule

$(A)\,\, KO_2$

$(B)\,\,$ cis $-[Co(en)_2Cl_2]^+$

$(C)\,\, K_3[Co(Ox)_3]$

$(D)\,\,[CoCl_3]^{2-}$

→
The standard electrode potentials $(E^o)$ for  $OCl^-/Cl^-$ and $\frac{1}{2}C{l_2}/C{l^ - }$ are $0.94\,V$ and $+1.36\,V$ respectively, the $E^o$ value for $OCl^-/\frac{1}{2}Cl_2$ will be ........... $\mathrm{V}$
→
Amongst the following, identify the species with an atom in $+6$ oxidation state
→
Phosphorus is manufactured by heating in a electric furnace a mixture of
→
If $O _{2}$ gas is bubbled through water at $303 \;K$, the number of millimoles of $O _{2}$ gas that dissolve in 1 litre of water is (Nearest Integer) (Given : Henry's Law constant for $O _{2}$ at $303 \;K$ is $46.82 \;k$ bar and partial pressure of $O _{2}=0.920 \;bar$ ) (Assume solubility of $O _{2}$ in water is too small, nearly negligible)
→
Consider the reactions, Identify $A, \,X,\, Y$ and $Z.$

$\underset{({{C}_{2}}{{H}_{6}}O)}{\mathop{X}}\,\,\xrightarrow[573\,\,K]{Cu}$  $A$  $\xrightarrow[^{-}OH\,,\,\Delta ]{{{[Ag{{(N{{H}_{3}})}_{2}}]}^{+}}}$ Silver mirror

$A\,\xrightarrow{^{-}OH\,,\,\Delta }Y$

$A\,\xrightarrow{N{{H}_{2}}NHCON{{H}_{2}}}Z$

→
Assertion : $[FeF_6]^{3-}$ is a low spin complex.

Reason : Low spin complexes have lesser number of unpaired electrons.

→
The enthalpy change for the reaction, $C_2H_6(g) \to 2C(g) + 6H(g)$ is $X\, kJ$. The bond energy of $C-H$ bond is :-
→