Chemistry Chapter: Covalent Bonds

Covalent Bonds Overview

• Covalent bonds form when atoms share electrons to achieve stability by completing their outer electron shells.
• Each shared pair of electrons represents one covalent bond.

Ammonia (NH3)

• Ammonia contains 3 covalent bonds formed between one nitrogen atom and three hydrogen atoms.
• Each hydrogen atom shares one electron with nitrogen, creating three shared pairs.

Nitrogen Molecule (N2)

• The nitrogen molecule consists of two nitrogen atoms sharing 6 electrons in total.
• Each nitrogen atom contributes 3 electrons to form 3 covalent bonds, achieving a full outer shell of 8 electrons.

Carbon Dioxide (CO2)

• Carbon dioxide has a total of 4 covalent bonds.
• One carbon atom binds with two oxygen atoms, sharing 4 electrons from carbon (4 valence electrons needed for stability) and 2 from each oxygen atom (6 valence electrons needing 2 more).
• Each covalent bond is depicted by a dash in the Lewis diagram.

Bromine Molecule (Br2)

• Bromine can form a diatomic molecule and each bromine atom has 7 outer electrons.
• Two bromine atoms share 2 electrons, creating 1 covalent bond and achieving stability with 8 electrons each in their outer shells (6 not shown in the shared orbit).

Hydrogen Cyanide (HCN)

• Hydrogen cyanide consists of one hydrogen, one carbon, and one nitrogen atom.
• Hydrogen shares 2 electrons with carbon, creating a single covalent bond.
• Carbon forms 4 covalent bonds: one with hydrogen and three with nitrogen.
• Each atom effectively has 8 electrons in its outer shell and is thus stable.

Lewis Dot Diagrams

• Lewis dot diagrams visually represent the covalent bonds and the number of electrons around each atom.
• The correct configuration for each compound illustrates how atoms achieve full outer shells through sharing electrons.

Test your knowledge of covalent bonds with this flashcard quiz focusing on ammonia (NH3) and its molecular structure. Understand how shared electron pairs represent covalent bonds and challenge yourself with multiple-choice questions.