Question

PLS ANSWER REALLY EASY! WILL MARK BRAINLIEST.

Answer 1

Explanation:

They are;

• The vertical columns of periodic table is called group and the horizontal rows of periodic table is called periods.
• The valance electron of all elements in the same group are the same but in periods the valance electron of elements in the same period increases from left to righr.
• The size of atoms increases top to bottom. but in case of periods the size of atoms decreases from left to right.
• Metalic reactivity increases and non metalic reactivity decreases from top to bottom. but in periods metalic reactivity decreases and non metalic reactivity increases from left to right.

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