The species which does not undergo disproportionation reaction is _______.

In reaction \(A + 2B\) \( \rightleftharpoons \) \(2C + D\), initial concentration of \(B\) was \(1.5\, times\) of \([A]\) , but at equilibrium the concentrations of \(A\) and \(B\) became equal. The equilibrium constant for the reaction is

The correct decreasing order of priority of functional groups in naming an organic compound as per \(IUPAC\) system of nomenclature is.

Which of the following pair is not isoelectronic species? (At. no. \(Sm , 62 ; Er , 68: Yb , 70: Lu , 71 ; Eu , 63: Tb\), \(65\); \(\operatorname{Tm}, 69)\)

The ammonia \((NH_{3} )\) released on quantitative reaction of \(0.6\; \mathrm{g}\) urea \(\left(\mathrm{NH}_{2} \mathrm{CONH}_{2}\right)\) with sodium hydroxide (\(NaOH\)) can be neutralized by

The energy required by electrons, present in the first Bohr orbit of hydrogen atom to be excited to second Bohr orbit is ___________ \(J~mol^{-1}\).
Given: \(R_{H}=2.18\times10^{-11}\) ergs

\(\mathrm{A}(\mathrm{g}) \rightarrow \mathrm{B}(\mathrm{g})+\mathrm{C}(\mathrm{g})\) is a first order reaction.
\(\begin{array}{|l|l|l|}\hline \text{Time} & T & \infty \\\hline \mathbf{P}_{\text {system }} & \mathrm{P}_{\mathrm{t}} & \mathrm{P}_{\infty} \\\hline\end{array}\)
The reaction was started with reactant A only. Which of the following expression is correct for rate constant k ?

Within a spherical charge distribution of charge density \(\rho \left( r \right)\), \(N\) equipotential surfaces of potential \({V_0},{V_0} + \Delta V,{V_0} + 2\Delta V,\)\(.....{V_0} + N\Delta V\left( {\Delta V > 0} \right),\) are drawn and have increasing radii \(r_0, r_1, r_2,......r_N\), respectively. If the difference in the radii of the surfaces is constant for all values of \(V_0\) and \(\Delta V\) then

The molarity of the solution prepared by dissolving \(6.3\, \mathrm{~g}\) of oxalic acid \(\left(\mathrm{H}_{2} \mathrm{C}_{2} \mathrm{O}_{4} \cdot 2 \mathrm{H}_{2} \mathrm{O}\right)\) in \(250\, \mathrm{~mL}\) of water in \(\operatorname{mol} \mathrm{L}^{-1}\) is \(\mathrm{x} \times 10^{-2} .\) The value of \(\mathrm{x}\) is ..... . (Nearest integer) [Atomic mass : \(\mathrm{H}: 1.0, \mathrm{C}: 12.0, \mathrm{O}: 16.0]\)

For the given cell ; \(Cu ( s )\left| Cu ^{2+}\left( C _{1} M \right) \| Cu ^{2+}\left( C _{2} M \right)\right| Cu ( s )\) change in Gibbs energy \((\Delta G )\) is negative, if :

n-Butane on monochlorination under photochemical condition gives an optically active compound "P". "P" on further chlorination gives dichloro compounds. The number of dichloro compounds obtained (ignore stereoisomers) is:

Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) :


Three identical spheres of same mass undergo one dimensional motion as shown in figure with initial velocities \(v_{\mathrm{A}}=5 \mathrm{~m} / \mathrm{s}, v_{\mathrm{B}}=2 \mathrm{~m} / \mathrm{s}, v_{\mathrm{C}}=4 \mathrm{~m} / \mathrm{s}\). If we wait sufficiently long for elastic collision to happen, then \(v_{\mathrm{A}}=4 \mathrm{~m} / \mathrm{s}, v_{\mathrm{B}}=2 \mathrm{~m} / \mathrm{s}\), \(v_{\mathrm{C}}=5 \mathrm{~m} / \mathrm{s}\) will be the final velocities.

Reason (R): In an elastic collision between identical masses, two objects exchange their velocities.
In the light of the above statements, choose the correct answer from the options given below :

The distance of the Sun from earth is \(1.5 \times 10^{11} \,m\) and its angular diameter is \((2000) \,s\) when observed from the earth. The diameter of the Sun will be ...........