The molecule with largest \(C - X\) bond length is

The rate of a first order reaction at a constant temperature

Match List I with List II:

List-I	List-ll
A. \(Fe ^{2+}\)	I. 2.84 BM
B. \(Ni ^{2+}\)	II. 0.00 BM
C. \(Mn ^{2+}\)	III. 4.90 BM
D. \(Zn ^{2+}\)	IV. 5.92 BM

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Answer the question on the basis of passage given below :
For the transition elements
Sc \(\quad\) Ti \(\quad\) V \(\quad\) Cr \(\quad\) Mn\(\quad\) Fe \(\quad\) Co \(\quad\) Ni \(\quad\) Cu \(\quad\) Zn
Atomic numbers :
21 \(\quad\) 22 \(\quad\) 23 \(\quad\) 24 \(\quad\) 25 \(\quad\) 26 \(\quad\) 27 \(\quad\) 28 \(\quad\) 29 \(\quad\) 30 \(\quad\)
Which transition element ion \(\text{M}^{3+}\) has electronic configuration \(3d^5 4s^0\)?

Arrange the following in decreasing order of the basic character in aqueous phase
(A) Ethanamine
(B) Benzeneamine
(C) Phenylmethanamine
(D) N-methylaniline
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A 0.5 M aqueous \(\mathrm{H}_2 \mathrm{SO}_4\) solution is diluted from 2 litres to 20 litres. The concentration of the resulting solution will be

Read the passage given below and answer the question.
The transition elements which give the greatest number of oxidation states occur in or near the middle of the series. Manganese, for example, exhibits all the oxidation states from +2 to +7 . The lesser number of oxidation states at extreme ends stems from either too few electrons to lose or share (Sc, Ti) on too many d-electrons (hence fewer orbitals available in which to share electrons with others) for higher valence \(( Cu , Zn )\). Thus early in the series scandium (II) is virtually unknown and titanium (IV) is more stable than Ti (III) or Ti (II). At the other end, the only oxidation state of zinc is \(+ 2\) (no d electrons are involved). The maximum oxidation states of reasonable stability correspond in value to the sum of the s - and d-electrons upto manganese ( \(Ti ^{I V} O _2, V^V O _2^{+}, Cr ^{V I} O _4^{2-}\), \(Mn ^{\text {VII }} O _4\) ) followed by a rather abrupt decrease in stability of higher oxidation states, so that the typical species to follow are \(Fe ^{I I, I I I}, Co ^{I I, I I I}, Ni ^{I I}, Cu ^{I, I I}, Zn ^{I I}\).
The variability of oxidation states, a characteristic of transition elements, arises out of incomplete filling of d-orbitals in such a way that their oxidation states differ from each other by unity, e.g. \(V ^{I I}, V^{I I I}, V^{I V}, V^V\). This is in contrast with the variability of oxidation states of non transition elements where oxidation states normally differ by a unit of two.
An interesting feature in the variability of oxidation states of the d-block elements is noticed among the groups (groups 4 through 10). Although in the p-block, the lower oxidation states are favoured by the heavier members (due to inert pair effect), the opposite is true in the groups of dblock. For example, in group 6, \(Mo ( VI )\) and \(W ( VI )\) are found to be more stable than \(Cr ( VI )\). The \(Cr ( VI )\) in the form of dichromate in acidic medium is a strong oxidising agent, whereas \(MoO _3\) and \(WO _3\) are not.
Low oxidation states are found when a complex compound has ligands capable of \(\pi\)-acceptor character in addition to the \(\sigma\)-bonding. For example, in \(Ni ( CO )_4\) and \(Fe ( CO )_5\), the oxidation state of nickel and iron is zero.
Identify the stable pair of ions :

Match List I with List - II.

List - 1	List - II
(A) Biocontrol agent	(I) Aphids
(B) Mycorrhiza	(II) Methanobacterium
(C) Ladybird	(III) Trichoderma
(D) Biogas	(IV) Glomus

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Which of the following statements is correct about the effect of the presence of a third charge on Coulomb force between the two charges?

The area bounded by the curve \(y=-x|x|\), the \(x\)-axis and the ordinates \(x=-1\) and \(x=1\) is given by:

Match List-I with List-II

List-I	List-II
(A) Electrical permittivity	(I) \(N m^2 C^{-1}\)
(B) Electric flux	(II) \(N^{-1} m^{-2} C^2\)
(C) Electric field	(III) \(Cm ^{-2}\)
(D) Surface charge density	(IV) \(N C^{-1}\)

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For a photoelectric effect:
(A) the photoelectric current is directly proportional to the intensity of the incident radiation.
(B) the maximum kinetic energy of the emitted photoelectrons increases linearly with the frequency of the incident radiation.
(C) for a given frequency of the incident radiation, the stopping potential increases linearly with the intensity of the incident radiation.
(D) the photoelectric emission is an instantaneous process without any apparent time lag.
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Arrange the following electromagnetic waves in the order of their decreasing frequency.
(A) Radio wave
(B) Gamma rays
(C) Ultraviolet ray
(D) Infrared wave
(E) Visible light
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