Chemistry, taken apart.

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AP Chemistry

9 chapters

Atomic structure and properties

the mole, the shell, the spectrum

A sodium atom in the shell model, its nucleus of protons and neutrons ringed by 2, 8 and 1 electrons with the lone valence electron in red, beside an orbital diagram filled to 1s² 2s² 2p⁶ 3s¹

Compound structure and properties

bonds and the shapes they make

An ammonia molecule: a blue nitrogen atom with three white hydrogens and a translucent red lone pair, labeled trigonal pyramidal

Properties of substances and mixtures

the forces between molecules

Liquid water: red-and-white water molecules tumbling, linked by red hydrogen bonds

Chemical reactions

equations and stoichiometry

A box of ammonia molecules, blue nitrogen with white hydrogens, beside one leftover N₂ molecule, under the equation N₂ + 3H₂ → 2NH₃

Kinetics

how fast, and by what path

A box of dark N₂O₅ molecules breaking down into blue NO₂ and gray O₂, beside graph paper where the falling N₂O₅ concentration carries a red tangent line

Thermochemistry

the heat of a reaction

A coffee-cup calorimeter with a thermometer at 28.8 °C beside a graph of temperature rising from 22 °C to 28.8 °C after mixing

Equilibrium

forward and back, balanced

A closed box of blue and red molecules beside graph paper where [A] and [B] level off and the forward and reverse rates meet

Acids and bases

protons, given and taken

A burette of NaOH over a flask of acetic acid turned pink, beside the titration curve with its half-equivalence point (pH = pKa) and equivalence point marked

Thermodynamics and electrochemistry

entropy, free energy and cells

A zinc–copper galvanic cell: electrons (red) travel through a wire and voltmeter reading 1.10 V from the zinc anode to the copper cathode in blue copper-ion solution, with ions moving through a salt bridge between the beakers