High school

Intro Chemistry

Free chemistry calculators for high school and first-year courses: molar mass, stoichiometry, pH and gas laws — each with worked steps and simulation mode.

  1. Molar Mass Calculator
    Calculate the molar mass of any molecule containing C, H, O, N, S and Cl atoms using 2021 IUPAC atomic weights. Free molecular weight calcul…
  2. Stoichiometry Calculator
    Calculate moles of reactant and product, theoretical yield and mole ratios from a balanced equation. Free chemistry stoichiometry calculator…
  3. Combined Gas Laws
    Verify PV=nRT, find predicted pressure and volume, and check ideal gas compressibility factor Z. Free gas law calculator for chemistry and p…
  4. pH Calculator
    Calculate pH, pOH, hydrogen ion and hydroxide concentrations for strong and weak acids. Includes percent dissociation and Ka-based weak acid…
  5. Ideal Gas Law
    Calculate pressure, volume or temperature using the ideal gas law PV=nRT. Supports Pa, kPa and atm outputs. Free chemistry and physics calcu…
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