Master foundational physics, finance, calculus, and engineering equations with live evaluators, derivations, and worked examples.
Relates absolute pressure, volume, molar quantity, and thermodynamic Kelvin temperature for dilute gases via universal gas constant R = 8.31446 J/(mol·K).
Quantifies the exponential sensitivity of chemical reaction rate constants k to activation energy barrier E_a and absolute temperature T.
Calculates the pH of aqueous weak-acid/conjugate-base buffer solutions and physiological bicarbonate equilibria.
Determines redox half-cell and battery open-circuit voltage away from standard 1 M conditions, as well as biological membrane equilibrium potentials.
Fundamental chemical thermodynamics criterion governing reaction spontaneity, maximum non-expansion work, and equilibrium constants at constant T and P.
Second-Law upper limit on thermal efficiency for any heat engine operating between hot reservoir T_H and cold sink T_C in Kelvin.
Analytical chemistry spectroscopy equation linking optical absorbance A linearly to molar absorptivity ε, cuvette path length l, and molar concentration c.