The chemistry and physics student
toolbox.
Balance equations, find molar masses and solve decay, optics and photon problems with clear working.
Keep this toolbox for offline use
17 useful places to start.
Atomic weights are rounded conventional values. Results state their assumptions, such as ideal conditions and vacuum wavelengths.
Molar mass calculator
Find the molar mass, element-by-element composition and moles of a chemical formula.
Chemical equation balancer
Balance a chemical equation with the smallest whole-number coefficients, including ions.
Half-life and decay calculator
Solve for remaining amount, elapsed time or half-life in exponential decay.
Snell’s law refraction calculator
Find the refraction angle, critical angle, Brewster angle and reflectance at an interface.
Photon energy and wavelength calculator
Convert between wavelength, frequency and photon energy in eV and joules.
pH, pOH & concentration
Relate pH, pOH and idealised hydronium/hydroxide concentrations using a stated pKw.
Weak acid buffer pH
Explore the Henderson–Hasselbalch model with a stated conjugate pair.
Molarity calculator
Calculate concentration from solute amount and final solution volume.
Solution dilution calculator
Calculate stock volume for a target concentration and final volume.
Ideal gas pressure calculator
Estimate absolute pressure from gas amount, volume and temperature.
Reaction percentage yield
Compare actual product yield with a supplied theoretical yield.
Scientific notation converter
Express a number in standard and scientific notation.
Significant figures calculator
Count significant figures, or round a number to a set number of significant figures or decimal places.
Periodic table element lookup
Find an element by name, symbol or atomic number, with its weight, group, block and electron configuration.
Empirical formula calculator
Find the simplest whole-number formula from percentage composition or masses, and the molecular formula from a molar mass.
Thin lens equation calculator
Solve for image distance, object distance or focal length, with magnification, image type and lens power.
Doppler effect calculator
Find the frequency an observer hears or sees when the source or observer moves, for sound and for light.
A few things you
can tick off.
- Balance a combustion equation
- Convert grams to moles
- Find the critical angle of glass