The position of elements with an outer electronic configuration as
$(n-2)<mspace\; width="1em"></mspace>f^7(n-1)d^{1}n{s}^2,<mspace\; width="1em"></mspace>n<mspace\; width="1em"></mspace>=<mspace\; width="1em"></mspace>\mathrm{6\; :}$

1. 6^th period and 10^th group

2. 7^th period and 3^rd group

3. 6^th period and 3^rd group

4. 7^th period and 9^th group

1st (∆H₁) and 2nd  (∆H₂) Ionization Enthalpies (in kJ mol^–1) and the (∆_egH) Electron Gain Enthalpy (in kJ mol^–1) of a few elements are given below:

The most reactive metal is:

Determine the formula of the stable binary compound that would be formed by an element having atomic number 71 and fluorine:

1. LuF₆

The factor that does not affect the valence electron is: 

The size of isoelectronic species: F^–, Ne and Na⁺, is affected by :

The incorrect statement about ionization enthalpy is:

Match the following isoelectronic species in Column-I and Column-II: 

Consider the graph given below and choose the correct answer:

The correct order of ionization energy of W, X, Y and Z is:

Consider the following curves:

X represents group with highest atomic radius. The element that belongs to Y group can be : 

In the following graph of variation of ionization energy with atomic number, X, Y, and Z represent elements.

The group number of X, Y, and Z elements is: