Question

Elements ‘X’ and ‘Y’ are adjacent elements in the s block of the periodic table. ‘X’ is on the left, and ‘Y’ is on the right. Provide a detailed comparison of all the periodic properties of ‘X’ and ‘Y’.

Answer 1

Step$1$: Find Elements ‘X’ and ‘Y’ that are adjacent elements in the s-block of the periodic table

• Alkali and Alkaline-earth metals are adjacent elements in the s-block of the periodic table.
• X-Alkali metals are on the left of the table.
• Y-Alkaline-earth metals are on the right of the table.

Step 2: Ionization energy and Electropositivity:

• Ionization energy is the energy required to remove an electron.
• Electropositive means the tendency of an atom to lose an electron.

Step 3: Comparison of all the periodic properties between ‘X’ and ‘Y’

Alkali metals:

• Alkali metals belong to the s-block elements occupying the leftmost side of group 1 of the periodic table.
• Alkali elements are Lithium(Li), Sodium(Na), Potassium (K), Rubidium (Ru), Cesium (Cs), and Francium (Fr) occupying successive periods from first to seven.
• Alkali metals readily lose electrons, making them count among the most reactive elements on earth.
• The electronic configuration of alkali-metals is [noble gas]$n{s}^1$
• They have low ionization enthalpy because of their larger atomic radii compare to alkaline-earth metals.
• So it readily loses an electron and becomes a noble gas configuration.
• Also has high electropositive because of the easy tendency to lose an electron.
• Because of this oxides of alkali metals are very basic in nature.
• Due to the highly electropositive nature of alkali metals, which makes these oxides highly ionic.
• Hence, they readily dissociate in water to give hydroxide ions.

Alkaline-earth metals:

• The alkaline earth metals are the elements that correspond to group 2 of the modern periodic table.
• This group of elements includes Beryllium (Be), Magnesium(Mg), Calcium (Ca), Strontium (Sr), Barium(Ba) and Radium (Ra).
• The electronic configuration for alkaline-earth metals is [noble gas] $n{s}^2$
• They have higher ionization enthalpy compared to alkali-metals because of their smaller radii.
• Also, it has two valence electrons. So its bonding is strong.
• It has low electropositive compared to alkali metals.
• The oxides of alkaline earth metals are quite basic but not as basic as those of alkali metals.
• This is because alkaline earth metals are less electropositive than alkali metals.

Hence, Alkali and Alkaline-earth metals are adjacent elements in the s-block of the periodic table.