please explain atomic size,atomic radius,electropositive and electronegative electrons,alkali matals and 
hollogens in relation with periods and groups.please explain these

Asked by manya.bhardwaj.01 | 18th Nov, 2017, 10:57: AM

Expert Answer:

Atomic size(Atomic radii)

Across a period

In a period, the size of an atom decreases from left to right. This is because the nuclear charge increases from left to right in the same period, thereby bringing the outermost shell closer to the nucleus.

Down a group

  In a group, the size of an atom increases as one proceeds from top to bottom. This is due to the successive addition of shells as we move from one period to the next in a group.


Electronegativity

Across a period

Electronegativity increases from left to right in a period, because the nuclear charge increases due to an increase in the atomic number.

Example: In the second period, electronegativity increases from Lithium to Fluorine.

Down a group

Electronegativity decreases down the group due to an increase in the atomic size overcoming the effect of an increase in the nuclear charge.

Answered by Varsha | 18th Nov, 2017, 02:03: PM

Queries asked on Sunday & after 7pm from Monday to Saturday will be answered after 12pm the next working day.