Unit 2: Molecular Representations & Functional Groups

Students succeed in organic chemistry when they can translate quickly between line structures, formulas, and functional-group language; every mechanism starts with correct pattern recognition.

• Interconvert molecular formula, condensed structure, bond-line drawing, and simple perspective representations.
• Calculate index of hydrogen deficiency and use it to estimate rings and pi bonds.
• Recognize the major functional-group families and connect each to a characteristic reactivity pattern.
• Apply basic IUPAC naming logic for common hydrocarbons and simple substituted compounds.

Checkpoint Questions

Q: What is the IHD of C6H10O2?

A: Two. Oxygen does not change the IHD calculation, so the formula behaves like C6H10 and corresponds to two rings/pi bonds in total.

Q: Why do bond-line structures make organic mechanisms easier to read than molecular formulas?

A: They show connectivity and functional groups directly, which makes electron flow and reaction sites visible.