$\mathrm{K}_2 \mathrm{Cr}_2 \mathrm{O}_7$ on heating with aqueous NaOH gives $\_\_\_\_$
$\mathrm{Cr}(\mathrm{OH})_2$
$\mathrm{Cr}(\mathrm{OH})_3$
$\mathrm{CrO}_4{ }^{2-}$
$\mathrm{CrO}_3$
In the photoelectric emission, the energy of the emitted electron is:
greater than the energy of the incident photon
smaller than the energy of the incident photon
same as that of the incident photon
proportional to the intensity of the incident photon
Identify the name of the reaction involved in conversion of $A \rightarrow B$ and name the compound $B$.
$$ \mathrm{CH}_3 \mathrm{CN} \xrightarrow[\mathrm{H}_2 \mathrm{O}]{\mathrm{H}^{+}} \mathrm{A}-\xrightarrow[\mathrm{H}^{+} / \mathrm{H}_2 \mathrm{O}]{\mathrm{Cl}_2 / \text { Red Phosphorous }} \mathrm{B} $$
Kolbe's reaction, Ethanoic acid
Esterification, methyl ethanoate
Hell-Volhard-Zelinsky reaction, 2-chloro-ethanoic acid
Riemer-Tiemann reaction, 1-chloro-ethanoic acid
The Crystal Field Stabilisation energy of (i) $\left[\mathrm{CoF}_6\right]^{3-}$ and (ii) $\left[\mathrm{Fe}\left(\mathrm{H}_2 \mathrm{O}\right)_6\right]^{3+}$ are ⋯and ⋯⋯ respectively.
(i) $-2.8 \Delta_0$ (ii) $-2.4 \Delta_0$
(i) $2.8 \Delta_0$ (ii) $2.4 \Delta_0$
COMEDK Papers
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