How many lone pairs of electrons does oxygen have in a water molecule?Group of answer choices1642

Understanding the Molecule

Water (H₂O) consists of two hydrogen (H) atoms and one oxygen (O) atom. To determine the number of lone pairs of electrons on the oxygen atom in a water molecule, we first need to account for the electron configuration of oxygen.

Valence Electrons of Oxygen

1. Valence Electrons: Oxygen, being in Group 16 of the periodic table, has six valence electrons.

Bonding in Water

2. Bond Formation: In a water molecule, oxygen forms two single bonds with the two hydrogen atoms. Each hydrogen atom contributes one electron, resulting in two of the oxygen’s six valence electrons being used in bonding.

Counting Lone Pairs

3. Remaining Electrons: After forming bonds with two hydrogen atoms, the oxygen atom has: $6 \text{ (total valence electrons)} - 2 \text{ (electrons used for bonding)} = 4 \text{ (remaining electrons)}$

4. Lone Pairs: The remaining four electrons can be paired into two lone pairs.

Verification and Summary

To summarize:

• The oxygen atom in a water molecule uses 2 electrons to bond with hydrogen.
• This leaves 4 electrons, which form 2 lone pairs.

Final Answer

Oxygen has 2 lone pairs of electrons in a water molecule.