Which of the following options are correct for the reaction \(2\left[ Au ( CN )_2\right]_{( aq )}^{-}+ Zn ( s ) \rightarrow 2 Au ( s )+\left[ Zn ( CN )_4\right]_{( aq )}^{2-}\) \(A.\) Redox reaction \(B.\) Displacement reaction \(C.\) Decomposition reaction \(D.\) Combination reaction Choose the correct answer from the options given below:

Match List - I with List - II.

List - I (Test)	List - II (Identification)
(A) Bayer's test	(I) Phenol
(B) Ceric ammonium nitrate test	(II) Aldehyde
(C) Phthalein dye test	(III) Alcoholic-OH group
(D) Schiff's test	(IV) Unsaturation

Choose the correct answer from the options given below :

The correct order of metallic character is:

Choose the correct tests with respective observations.
(A) \(\mathrm{CuSO}_4\) (acidified with acetic acid) \(+ \mathrm{K}_4\left[\mathrm{Fe}(\mathrm{CN})_6\right] \rightarrow\) Chocolate brown precipitate.
(B) \(\mathrm{FeCl}_3+\mathrm{K}_4\left[\mathrm{Fe}(\mathrm{CN})_6\right] \rightarrow\) Prussian blue precipitate.
(C) \(\mathrm{ZnCl}_2+\mathrm{K}_4\left[\mathrm{Fe}(\mathrm{CN})_6\right]\), neutralised with \(\mathrm{NH}_4 \mathrm{OH}\) \(\rightarrow\) White or bluish white precipitate.
(D) \(\mathrm{MgCl}_2+\mathrm{K}_4\left[\mathrm{Fe}(\mathrm{CN})_6\right] \rightarrow\) Blue precipitate.
(E) \(\mathrm{BaCl}_2+\mathrm{K}_4\left[\mathrm{Fe}(\mathrm{CN})_6\right]\), neutralised with NaOH \(\rightarrow\) White precipitate.
Choose the correct answer from the options given below :

According to molecular orbital theory, the number of unpaired electron(s) in \(\mathrm{O}_{2}^{2-}\) is :

Maximum number of electrons that can be accommodated in shell with \(n=4\) are:

In an acid -base titration, \(0.1\, M\, HCl\) solution was added to the \(NaOH\) solution of unknown strength. Which of the following correctly shows the change of \(pH\) of the titration mixture in this experiment?

Preeti reached the metro station and found that the escalator was not working. She walked up the stationary escalator in time \(t_1\) . On other days, if she remains stationary on the moving escalator, then the escalator takes her up in time \(t_2\). The time taken by her to walk up on the moving escalator will be 

A solid sphere of radius \(R\) carries a charge \((Q+q)\) distributed uniformly over its volume. A very small point like piece of it of mass \(m\) gets detached from the bottom of the sphere and falls down vertically under gravity. This piece carries charge \(q.\) If it acquires a speed \(v\) when it has fallen through a vertical height \(y\) (see figure), then : (assume the remaining portion to be spherical).

Identify the correct statements from the following
A. \([Fe(C_2O_4)_3]^{3-}\) is the most stable complex among \([Fe(OH)_6]^{3-}\), \([Fe(C_2O_4)_3]^{3-}\) and \([Fe(SCN)_6]^{3-}\)
B. The stability of \([Cu(NH_3)_4]^{2+}\) is greater than that of \([Cu(en)_2]^{2+}\)
C. The hybridization of Fe in \(K_4[Fe(CN)_6]\) is \(d^2sp^3\)
D. \([Fe(NO_2)_3Cl_3]^{3-}\) exhibits linkage isomerism
E. \(NO_2^-\) and \(SCN^-\) ligands are NOT ambidentate ligands
Choose the correct answer from the options given below :

The energy density associated with electric field \(\overrightarrow{ E }\) and magnetic field \(B\) of an electromagnetic wave in free space is given by ( \(\epsilon_0-\) permittivity of free space, \(\mu_0\) - permeability of free space)

The correct match between item \(I\) and item \(II\) is

Item \(I\)	Item \(II\)
\((a)\) Benzaldehyde	\((p)\) Mobile phase
\((b)\) Alumina	\((q)\) Adsorbent
\((c)\) Acetonitrile	\((r)\) Adsorbate

The mean and variance of \(7\) observations are \(8\) and \(16\) respectively. If two observations are \(6\) and \(8 ,\) then the variance of the remaining \(5\) observations is: