Use the periodic table in answer the given questions.
(1) Identify an element with 5 electrons in outer subshell.
(2) Identify an element that would tend to lose 2 electrons.
(3) Identify a element that would tend to gain 2 lectrons.

Explanation

(1) Fluorine. Its configuration is `1s^(2)2s^(2)2p^(5)`.
(2) Magnesium. Its configuration is `1s^(2)2s^(2)2p^(6)3s^(2)`. So, Mg loses 2 electrons from its outermost shell to form `Mg^(2+)` and attains stable configuration.
(3). Oxygen. Its configuration is `1s^(2)2s^(2)2p^(4)` So, O gains 2 electrons to form `O^(2-)` and attains stable configuration.