Chemistry: Lewis Structures, Molecular Geometry and Polarity

Front

What is a Lewis structure?

Back

A Lewis structure is a diagram that shows the bonding between atoms of a molecule and the lone pairs of electrons that may exist in the molecule.

Front

What does the octet rule state?

Back

The octet rule states that atoms tend to bond in such a way that they have eight electrons in their valence shell, achieving a stable electron configuration.

Front

What is electronegativity?

Back

Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons.

Front

What is the difference between ionic and covalent bonds?

Back

Ionic bonds involve the transfer of electrons from one atom to another, while covalent bonds involve the sharing of electrons between atoms.

Front

What is a polar molecule?

Back

A polar molecule is a molecule that has a net dipole moment due to the presence of polar bonds, which arise from differences in electronegativity between bonded atoms.

Front

What is the significance of ΔEN (difference in electronegativity)?

Back

ΔEN helps determine the type of bond between two atoms: a large ΔEN indicates an ionic bond, a moderate ΔEN indicates a polar covalent bond, and a small ΔEN indicates a nonpolar covalent bond.

Front

What is the molecular geometry of PBr3?

Back

The molecular geometry of PBr3 is trigonal pyramidal due to the presence of a lone pair on the phosphorus atom.

Front

How do you determine the polarity of a molecule?

Back

To determine the polarity of a molecule, assess the electronegativity differences between atoms and the molecular geometry to see if there is an uneven distribution of charge.

Front

What is the role of lone pairs in Lewis structures?

Back

Lone pairs in Lewis structures represent pairs of valence electrons that are not involved in bonding and can affect the shape and polarity of the molecule.

Front

What is the bond angle in a tetrahedral molecular geometry?

Back

The bond angle in a tetrahedral molecular geometry is approximately 109.5 degrees.