Question

Statement I: Along the period, the chemical reactivity of the element gradually increases from group 1 to group 18.
Statement II: The nature of oxides formed by group 1 element is basic while that of group 17 elements is acidic.
In the light of the above statements, choose the most appropriate from the questions given below:

• A. Both statement-I and statement-II are true
• B. Statement-I is true and statement-II is false
• C. Statement-I is false and statement-II is true
• D. Statement-I and statement-II both are false

Answer 1

The Correct Option is C

Statement I is incorrect. Chemical reactivity does not exhibit a consistent increase across a period. Specifically:

For metals on the left of the periodic table, chemical reactivity diminishes from left to right due to rising ionization energy.

For nonmetals on the right of the periodic table, chemical reactivity escalates from left to right, attributable to increased electronegativity and electron affinity.

Consequently, chemical reactivity lacks a uniform trend across a period, rendering the statement false.

Statement II is correct. Oxides formed by:

• Group 1 elements (alkali metals) are basic, as exemplified by Na₂O and K₂O, which produce strong bases like NaOH upon reaction with water.
• Group 17 elements (halogens) are acidic, with oxides such as Cl₂O₇ forming strong acids like HClO₄ when reacting with water.

Therefore, Statement II is true.

In summary, Statement I is false and Statement II is true. The correct option reflects this evaluation.