The incorrect order of radius is :

\(1.~~\mathrm{Sr}^{2+}<{\mathrm{Rb}}^{+}<{\mathrm{Br}}^{-}<\mathrm{Se}^{2-}\)
2. \( \mathrm{Nb}^{5+}<\mathrm{Zr}^{4+}<\mathrm{Y}^{3+}\)
3. \(\mathrm{Co}>\mathrm{Co}^{2+}>\mathrm{Co}^{3+}>\mathrm{Co}^{4+}\)
4. \(\mathrm{Ba}^{2+}<\mathrm{Cs}^{+}<\mathrm{Se}^{2-}<\mathrm{As}^{3-} \)

The radius of which ion is closest to that of $L{i}^{+}$ ion ?

1. $N{a}^{+}$                                       

2. $B{e}^{2+}$

3. $M{g}^{2+}$                                       

4. $A{l}^{3+}$

The correct order of ${\mathrm{IE}}_2$ is:

(1) Ne>F>O>N                     

(2) O>F>Ne>N

(3) Ne>O>F>N                     

(4) O>Ne>F>N

Which of the following transformation least energy is required?

(1) ${F^{-}}_{\left(g\right)<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>}\to F_{\left(g\right)}<mspace\; width="1em"></mspace>+e^{-}$                 

(2) ${P^{-}}_{\left(g\right)}\to P_{\left(g\right)}+e^{-}$

(3) ${S^{-}}_{\left(g\right)}\to S_{\left(g\right)}+e^{-}$                   

(4) $C{l^{-}}_{\left(g\right)}\to C{l}_{\left(g\right)}+e^{-}$

Which of the following represents correct order of electron affinity?

(1) Cl>F>S>O                           

(2) F>O>S>Cl

(3) F>Cl>S>O                           

(4) Cl>S>O>F

Correct expression of "Allred and Rochow's" scale is:

(a) Electronegativity =$0.744\frac{Z_{eff.}}{r^2}+0.359$

(b) Electronegativity =$0.359\frac{r^2}{Z_{eff.}}+0.744$

(c) Electronegativity =$0.359\frac{Z_{eff.}}{r}+0.744$

(d) Electronegativity =$0.359\frac{Z_{eff.}}{r^2}+0.744$

The process that requires absorption of energy is:

1. $N\to N^{-}$                       

2. $F\to F^{-}$

3. $Cl\to C{l}^{-}$                     

4. $H\to H^{-}$

Which of the following compound is most acidic?

1. $C{l}_2{O}_7$                              2. $P_4{O}_{10}$

3. $S{O}_3$                                 4. $B_2{O}_3$

If P and T are second period p-block elements then which of the following graph show correct relation between valence electrons in $P_2$ to $T_2$ (corresponding molecules) and their bond order is :

(a)                                                  

(b) 

(c)                                            

(d) 

Consider the following four elements, which are represented according to long form of periodic table.

Here W, Y and Z are left, up and right elements with respect to the element 'X' and 'X' belongs to 16th group and 3rd period. Then according to given information the incorrect statement regarding given elements is:

1. Maximum electronegativity :Y             

2. Maximum catenation property :X

3. Maximum electron affinity :Z               

4. Y exhibits variable covalency