Organic Groups and Molecular Structure
You'll need to master the different organic functional groups to succeed in chemistry. Alcohols contain the OH (hydroxyl) group with the formula CₙH₂ₙ₊₁OH, whilst haloalkanes have group 7 elements like chlorine or bromine attached. Ethers are simpler - they just have a single oxygen atom stuck in the middle of an alkane chain.
Learning the naming prefixes is absolutely essential for exams. The sequence "meth, eth, prop, but, pent, hex, hept, oct, non, dec" tells you how many carbon atoms are present (1 to 10 respectively). When you see multiple double bonds, add "diene" for two or "triene" for three.
Molecular shapes depend entirely on the bonding around carbon atoms. Single bonds create a tetrahedral shape (109.5°), whilst double bonds form a trigonal planar structure (120°). Remember that sigma bonds (direct overlap) are always stronger than pi bonds (sideways overlap).
Quick tip: The "Monkeys Eat Peanut Butter" mnemonic helps you remember meth-eth-prop-but!
Isomerism might seem tricky, but it's just about molecules with the same atoms arranged differently. Structural isomers have different structural formulas, whilst stereoisomers have the same structural formula but different 3D arrangements. E/Z isomerism occurs because double bonds can't rotate freely.
