Test: Classification of Elements and Periodicity in Properties (June 9) - NEET MCQ

Amongst isoelectronic ions, the size of the cation decreases as the magnitude of the charge increases.

N, O and F (p-block elements) are highly electronegative non metals and will have the strongest tendency to form anions by gaining electrons from metal atoms.

First ionisation potential of Be is greater than boron due to following configuration ₄Be=1s²,2s² ₅B=1s²,2s²2p¹ Order of attraction of electrons towards nucleus 2s>2p, so more amount of energy is required to remove the electron with 2sorbital in comparison to 2p orbital.

A. B. D are the configuration of Zn, Cd and Hg respectively which belongs to the same family. But c is the configuration of chlorine which belongs to halogen family.

This is because of inter-electronic replusions between lone pairs.

For i soelectronic species, size of anion increases as negative charge increases whereas size of cation decreases with increase in positive charge. Further ionic radii of anions is more than that of cations. Thus the correct order is          
Ca⁺⁺ < K⁺ < Ar < Cl^– < S^{– –}

Be – 1s²2s²; B – 1s²2s²2p1; C – 1s²2s²2p²; N – 1s²2s²2p³; O – 1s²2s²2p⁴. IP increases along the period. But IP of Be > B. Further IP of O < N because atoms with fully  or partly filled orbitals are most stable and hence have high ionisation energy.

Greater is the positive charge on atom, large is effective nuclear charge. Hence smaller is the size

The electronic configuration of element with atomic number 33 is 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p³
As, its last shell have five electrons
and hence, its group is 10 + 5 = 15th or V A.
Hence,it lies in the 15th group.
 

Abnormally high difference between 2nd and 3rd ionization energy means that the element has two valence electrons, i.e., configuration (d)

Electronic configuration of element with atomic number 118 will be [Rn]5f¹⁴6d¹⁰ 7s²7p⁶. Since its elctronic configuration in the outer most orbit (ns²np⁶) resemble with that of inert or noble gases, therefore it will be noble gas element.

Along the period, I.P. generally increases but not regularly. Be and B are exceptions. First I.P. increases in moving from left to right in a period, but I.P. of B is lower than Be.

Due to odd number of electr on s in ClO₂.

Therefore   

Non-metal like halogens are strongest oxidizing agents according to electrochemical series they form acidic oxides like SO₂ they form anion by electron gain and they are highly electronegative.
(fluorine is most electronegative element of whole periodic table)

Metallic character decreases in a period and increases in a group.