Free Chemistry tool · Step by step

Stoichiometry Solver

Balance the reaction, then convert grams or moles of one substance into another with the mole ratio shown step by step. Free stoichiometry solver for GCSE, AP Chemistry and JEE/NEET.

Answer

m(H2O)=35.74 gm(\mathrm{H_{2}O}) = 35.74\ \mathrm{g}

35.74 g of H2O (1.984 mol)

  1. 1

    Balance the equation

    The equation as entered is already balanced.

    2 H2+O2→2 H2O2\,\mathrm{H_{2}} + \mathrm{O_{2}} \rightarrow 2\,\mathrm{H_{2}O}
  2. 2

    Molar mass of H2

    M(H2)=2(1.008)=2.016 g/molM(\mathrm{H_{2}}) = 2(1.008) = 2.016\ \mathrm{g/mol}
  3. 3

    Convert grams to moles

    n(H2)=4 g2.016 g/mol=1.984 moln(\mathrm{H_{2}}) = \frac{4\ \mathrm{g}}{2.016\ \mathrm{g/mol}} = 1.984\ \mathrm{mol}
  4. 4

    Mole ratio from the coefficients

    From the balanced equation, 2 mol H2 corresponds to 2 mol H2O.

    n(H2O)n(H2)=22\frac{n(\mathrm{H_{2}O})}{n(\mathrm{H_{2}})} = \frac{2}{2}
  5. 5

    Moles of H2O

    n(H2O)=1.984 mol×22=1.984 moln(\mathrm{H_{2}O}) = 1.984\ \mathrm{mol} \times \frac{2}{2} = 1.984\ \mathrm{mol}
  6. 6

    Convert moles of H2O to grams

    M(H2O) = 18.015 g/mol.

    m(H2O)=1.984 mol×18.015 g/mol=35.74 gm(\mathrm{H_{2}O}) = 1.984\ \mathrm{mol} \times 18.015\ \mathrm{g/mol} = 35.74\ \mathrm{g}

AI video explanation

Want a 1-minute AI video explanation, or have a harder homework screenshot?

Doubtclip turns the question into a step-by-step whiteboard video with voice.

Click here — solve with AI

FAQ

What is the stoichiometry roadmap?

grams A → moles A (÷ molar mass) → moles B (× mole ratio) → grams B (× molar mass).

Does it balance the equation first?

Yes — the mole ratio always comes from the balanced equation.

More free tools

ChemistryChemical Equation BalancerBalanced coefficients plus an element-by-element atom count check.ChemistryMolarity CalculatorMolarity, mass or volume with molar mass worked out from the formula.MathQuadratic Formula CalculatorDiscriminant, nature of roots and both roots with every step shown.MathDerivative & Integral CalculatorRule-by-rule derivatives and integrals for polynomials, trig, exp and log.