Magnesium reacts with an element (X) that has a ground state electronic configuration of 1s²2s²2p³. What is the simplest formula for the ionic compound formed?

1. Mg₂X₃
2. MgX₂
3. Mg₂X
4. Mg₃X₂

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

$1. \mathrm{Ar} < {\mathrm{K}}^{+} < {\mathrm{Ca}}^{2+}$
$2. {\mathrm{Ca}}^{2+} < \mathrm{Ar} < {\mathrm{K}}^{+}$
$3. {\mathrm{Ca}}^{2+} < {\mathrm{K}}^{+} < \mathrm{Ar}$
$4. {\mathrm{K}}^{+} <\hspace{0.17em}\mathrm{Ar} < {\mathrm{Ca}}^{2+}$

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

1. $H^{-}>H^{+}>H$

2. $N{a}^{+}>F^{-}>O^{2-}$

3. $F^{-}>O^{2-}>N{a}^{+}$

4. $N^{3-}>M{g}^{2+}>A{l}^{3+}$

Which of the following statements is incorrect?

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

1. Cl<F<O<S

2. O<S<F<Cl

3. F<S<O<Cl

4. S<O<Cl<F

 An amphoteric hydroxide among the following is : 

1.  $\mathrm{Be}{\left(\mathrm{OH}\right)}_2$

2.  $\mathrm{Sr}{\left(\mathrm{OH}\right)}_2$

3.  $\mathrm{Ca}{\left(\mathrm{OH}\right)}_2$

4.  $\mathrm{Mg}{\left(\mathrm{OH}\right)}_2$

The element having electronic configuration [Kr]4d¹⁰4f¹⁴, 5s²5p⁶, 6s² belongs to:

1. s-block

2. p-block

3. d-block

4. f-block

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

1. s-block element

2. p-block element

3. d-block element

4. Transition element