Here are formulae that I can think of from the top of my head:
n = cv
n = M/m
pH = -log10[H+]
∆H = mC∆T
n = number of moles, c = concentration or molarity (mol/L), M = mass (g), m = molecular mass, m = mass, C = specific heat capacity of substance/solid, ∆H = molar heat of combustion, ∆T = change in temperature (final temperature - initial temperature)