Atomic radius of Be, O, C, N, B are respectively (in pm) :-

(1) 111, 66, 77, 74, 88

(2) 74, 84, 111, 77, 66

(3) 111, 88, 77, 74, 66

(4) 111, 66, 88, 77, 74

Which of the following orders of ionic radii is correctly represented?

(1) H^->H>H+

(2) Na⁺>F^->O^2-

(3) F^->O^2->Na⁺

(4) Al³⁺>Mg²⁺>N^3-

Identify the wrong statement in the following:

(1) Amongst isoelectronic species, smaller the positive charge on the cation, smaller is the ionic radius

(2) Amongst isoelectronic species, greater the negative charge on the anion, larger is the ionic radius

(3) Atomic radius of the elements increases as one moves down the first group of the Periodic Table

(4) Atomic radius of the elements decreases as one moves across from left to right in the 2nd period of the Periodic Table

Which of the following represents the correct order of increasing electron gain enthalpy with negative sign for the elements O, S, F and Cl?

(a) Cl<F<O<S                   (b) O<S<F<Cl

(c) F<S<O<Cl                   (d) S<O<Cl<F

An element whose IUPAC name is ununtrium(Uut) belong to:

(1) s-block element                               

(2) p-block element

(3) d-block element                               

(4) Transition element

Consider the following electronic configuration of an element (P) :

$\left[\mathrm{Xe}\right]4f^{14}5d^{1}6s^2$

Then correct statement about element 'P' is :

(1) It belongs to 6th period and the 1st group

(2) It belongs to 6th period and the 2nd group

(3) It belongs to 6th period and the 3rd group

(4) none of these 

Consider the following information about element P and Q :

                        Period number            Group number

P                               2                                 15

Q                               3                                 2

Then formula of the compound formed by P and Q element is :

(1) PQ         

(2) $P_3{Q}_2$           

(3) $P_2{Q}_3$           

(4)$P{Q}_2$

Which of the following properties of the alkaline earth metals increase from Be to Ba?

(i) Atomic radius       
(ii) Ionisation energy       
(iii) Nuclear charge

1. (i) and (ii)                                 

2. (i) and (iii)

3. (ii) and (iii)                               

4. (i), (ii) and (iii)

Aqueous solutions of two compounds $M_1-O-H and M_2-O-H$ are prepared in two different beakers. If, the electronegativity of $M_1=3.4 , M_2=1.2, O=3.5 and H=2.1,$ then the nature of two solutions will be respectively:

(a) acidic, basic             (b) acidic, acidic

(c) basic, acidic             (d) basic, basic

The process requiring the absorption of energy is:

1. $F\to F^{-}$

2. $H\to H^{-}$

3. $Cl\to C{l}^{-}$

4. $O\to O^{2-}$