Question

what change is observed across a period and down a group in the following​

Answer 1

Answer:

Write the full question please..

Answer 2

Answer:

So, as you move down a group on the periodic table, the electronegativity of an element decreases because the increased number of energy levels puts the outer electrons very far away from the pull of the nucleus. Electronegativity increases as you move from left to right across a period on the periodic table.