Given below are two statements: 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 the light above statements, choose the most appropriate from the questions given below:

Step-by-step solution

The atomic and ionic radii, as we know, generally decrease in a period from left to right. As a consequence, the ionisation enthalpies generally increase (with some exceptions) and electron gain enthalpies become more negative across a period. In other words, the ionisation enthalpy of the extreme left element for a period is the least and the electron gain enthalpy of the element on the extreme right is the highest negative (Note: noble gases having completely filled shells have rather positive electron gain entha