Question #3ca57

1 Answer
Apr 21, 2017

Because Na atom has extra electron

Explanation:

When we are talking of a #Na^+# ion we are talking of a #Na# atom with 1 less electron
enter image source here

while an Na atom has

enter image source here

an extra electron which is the only one present in its last accessible orbital thus covering more space.If you think it as a circle.consider nucleus as the center of the circle

enter image source here

Whereas in Na atom

enter image source here