Why do atoms lose/gain/share electrons in chemical reactions?Group of answer choicesTo neutralise charge of the atomTo increase atomic sizeTo achieve a fully filled valence shell

Atoms lose, gain, or share electrons in chemical reactions primarily to achieve a fully filled valence shell. This is known as the Octet Rule, which states that atoms are most stable when their outermost (valence) electron shell is full, typically with eight electrons.

1. Losing Electrons: Metals tend to lose electrons in order to achieve a full valence shell. For example, sodium (Na) has one electron in its outermost shell. It can lose this electron to have a full valence shell, becoming a positively charged ion (Na+).

2. Gaining Electrons: Non-metals, on the other hand, tend to gain electrons to achieve a full valence shell. For example, chlorine (Cl) has seven electrons in its outermost shell. It can gain one electron to have a full valence shell, becoming a negatively charged ion (Cl-).

3. Sharing Electrons: Atoms can also share electrons to achieve a full valence shell. This typically happens between non-metals. For example, two hydrogen atoms can share their single electrons to form a covalent bond, with the shared electrons counting towards both atoms' valence shells.

The goal of achieving a full valence shell is to reach a state of lower potential energy, which is a more stable state. This is the primary reason why atoms participate in chemical reactions.