OnRamps Midterm U2 Review

Front

What is resonance in chemistry?

Back

Resonance refers to the phenomenon where a molecule can be represented by two or more valid Lewis structures, indicating that the actual structure is a hybrid of these forms.

Front

Which compound exhibits resonance?

Back

CO₃²⁻ (carbonate ion) exhibits resonance due to its multiple valid Lewis structures.

Front

How many lone pairs are in PF₃?

Back

PF₃ has 1 lone pair on the phosphorus atom.

Front

What is the molecular geometry of H₂O?

Back

H₂O has an angular (bent) molecular geometry due to the two lone pairs on oxygen.

Front

Identify the incorrectly assigned molecular geometry: BCl₃, trigonal pyramidal.

Back

BCl₃ has a trigonal planar geometry, not trigonal pyramidal.

Front

What is an expanded valence shell?

Back

An expanded valence shell occurs when an atom can accommodate more than eight electrons in its outer shell, typically seen in elements from the third period and beyond.

Front

Which molecular geometry is not associated with an expanded valence?

Back

Trigonal pyramidal is not associated with an expanded valence; it typically involves atoms with a maximum of eight electrons.

Front

What is the ΔEN range for ionic bonds?

Back

Ionic bonds typically have a ΔEN (difference in electronegativity) greater than 1.7.

Front

What is the ΔEN range for non-polar covalent bonds?

Back

Non-polar covalent bonds have a ΔEN of 0.

Front

What is the ΔEN range for polar covalent bonds?

Back

Polar covalent bonds have a ΔEN greater than 0 but less than 1.7.