The \(\mathrm{E}^{\circ}\) value for the \(\mathrm{Mn}^{3 *} / \mathrm{Mn}^{2+}\) couple is more positive than that of \(\mathrm{Cr}^{3+} / \mathrm{Cr}^{2+}\) or \(\mathrm{Fe}^{3+} / \mathrm{Fe}^{2 *}\) due to change of

If radius of second Bohr orbit of the \(He ^{+}\)ion is \(105.8\,pm\), what is the radius of third Bohr orbit of \(Li ^{2+}\) ion?

Match List I with List II :

List-I	List-II
(A)	(I) (i) oleum; (ii) \(H _2 O / H ^{+}\) (iii) \(H ^{+}\)
(B)	(II) (i) \(O _2\); (ii) \(H _2 O / H ^{+}\)
(C)	(III) (i) \(CH _3 OH , H ^{+}\); (ii) \(H _2\), catalyst
(D)	(IV) (i) conc. \(H _2 SO _4, \triangle\); (ii) \(H ^{+} / H _2 O\)

Choose the correct answer from the options given below:

The reason for greater range of oxidation states in actinoids is attributed to

The pair of lanthanoid ions which are diamagnetic is

An example of a sigma bonded organometallic compound is

Consider the following reaction for which the change in enthalpy is positive \(2 A ( g ) + B ( g ) \rightleftharpoons C ( g )+ D ( g )\) Which of the following will not affect the equilibrium?

Given below are two statements: one is labelled as Assertion \(A\) and the other is labelled as Reason \(R\). Assertion \(A\): The potential ( \(V\) ) at any axial point, at \(2 \mathrm{~m}\) distance ( \(r\) ) from the centre of the dipole of dipole moment vector \(\vec{P}\) of magnitude, \(4 \times 10^{-6} \mathrm{C} \mathrm{m}\), is \(\pm 9 \times 10^3 \mathrm{~V}\). (Take \(\frac{1}{4 \pi \epsilon_0}=9 \times 10^9 \mathrm{Sl}\) units) Reason \(R\): \(V= \pm \frac{2 P}{4 \pi \epsilon_0 r^2}\), where \(r\) is the distance of any axial point, situated at \(2 \mathrm{~m}\) from the centre of the dipole. In the light of the above statements, choose the correct answer from the options given below:

The compound which shows metamerism is :

Which of the following is correct about viroids?

In a double slit experiment, when light of wavelength \(400\; nm\) was used, the angular width of the first minima formed on a screen placed \(1 \;\mathrm{m}\) away, was found to be \(0.2^{\circ} .\) What will be the angular width of the first minima, if the entire experimental apparatus is immersed in water.......\(^o\) \((\mu_{water } =4 / 3 )\)

Match List I with List II related to muscular/skeletal system :

List I	List II
A. Tetany	I. Inflammation of joints
B. Arthritis	II. Autoimmune disorder affecting neuromuscular junction
C. Myasthenia gravis	III. Wild contraction in muscle due to low \(Ca ^{++}\)in body fluid
D. Muscular dystrophy	IV. Progressive degeneration of skeletal muscle

Choose the correct answer from the options given below :

A metal rod of \(1\; m\) length, is dropped exact vertically on to a hard metal floor. With an oscilloscope, it is determined that the impact produces a longitudinal wave of \(1.2 \;k Hz\) frequency. The speed of sound in the metal rod is