Which of the following has the highest electronegativity?

1.	Carbon	2.	Oxygen
3.	Boron	4.	Fluorine

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

Which of the following orders is correct for the given properties?

1. F > Cl > Br > I (Electron affinity)

2. I^-> I > I⁺ (Ionisation Energy)

3. I^-> I > I⁺ (Atomic/ionic radii)

4. I⁺⁷ > I⁺ > I⁺⁵ (Ionisation Energy)

The element with atomic number 26 is:

1. A non-metal

2. Krypton

3. Iron

4. Manganese

Zn and Cd do not show variable valency like 'd' block elements due to :

1. Softness

2. Completed 'd' orbital

3. Two electrons in outermost orbit

4. Low m.p.

Match the name of elements given in list-I with the corresponding electronic configuration given in list-II and select the correct answer using the codes given below:

Codes :

The species Ar, K⁺ and Ca²⁺ contain the same number of electrons. In which order do their radii increase?
1.  Ar < K⁺ < Ca²⁺
2. Ca²⁺ < Ar < K⁺
3. Ca²⁺ < K⁺ < Ar
4. K⁺ < Ar < Ca²⁺

Which ion is isoelectronic with Be²⁺?

Among ${\mathrm{P}}_2{\mathrm{O}}_5,<mspace\; width="1em"></mspace>{\mathrm{As}}_2{\mathrm{O}}_3,<mspace\; width="1em"></mspace>{\mathrm{Sb}}_2{\mathrm{O}}_3<mspace\; width="1em"></mspace>\mathrm{and}<mspace\; width="1em"></mspace>{\mathrm{Bi}}_2{\mathrm{O}}_3$, the most acidic oxide is:

1.  $P_2{O}_5$

2.  $A{s}_2{O}_3$

3.  $S{b}_2{O}_3$

4.  $B{i}_2{O}_3$

The first four ionization energy values of a metal are 191, 587, 872, and 5962 kcal/mol respectively. The number of valence electrons in the element is/are:

1.  1

2.  2

3.  3

4.  5