Chemistry & Biochemistry
Chemical calculations, stoichiometry, and molecular analysis tools with detailed explanations.
Our chemistry calculators help students and researchers perform accurate chemical calculations. From balancing equations to calculating pH and buffers, each tool provides step-by-step solutions. You might also find our Calculate solution concentrations, Prepare lab dilutions, Understand heat effects, Analyze titration data, Find reaction correlations, Track chemistry grades, Calculate measurement errors and Measure solution absorbance helpful for related calculations.
Chemistry & Biochemistry Guide
Last updated: February 16, 2026
Last updated: February 16, 2026
What you can do in Chemistry & Biochemistry
- •Calculate molar mass and percent composition for any chemical formula
- •Balance chemical equations using algebraic and redox methods
- •Determine limiting reagents, theoretical yield, and percent yield in reactions
- •Calculate pH, pOH, Ka, and Kb for acids, bases, and buffer solutions
- •Plan dilutions using C₁V₁=C₂V₂ with serial dilution support
- •Analyze ideal gas problems with PV=nRT and combined gas law calculations
Accuracy, assumptions, and sources
- •Atomic weights use IUPAC 2021 standard values. Isotopically enriched samples may require manual adjustment.
- •pH calculations assume 25°C and dilute aqueous solutions. Ion activity coefficients are approximated as 1.
- •Stoichiometry assumes complete reactions unless percent yield is specified.
- •Ideal gas calculations assume PV=nRT behavior. Real gas deviations occur at high P or low T.
- •Buffer calculations use Henderson-Hasselbalch equation, valid within ±1 pH unit of pKa.
- •Dilution calculations assume volumes are additive (ideal mixing). Concentrated solutions may deviate.
Pick the right calculator fast
- If you need the molecular weight of a compound→Molar Mass Calculator
- If you're balancing a chemical equation→Chemical Equation Balancer
- If you need to find limiting reagent or yield→Stoichiometry Calculator
- If you're calculating pH or working with acids/bases→pH & pOH Calculator
- If you need to prepare a buffer solution→Buffer Maker Calculator
- If you're solving gas law problems→Ideal Gas Law Calculator
- If you need to dilute a stock solution→Dilution Calculator
- If you want elemental composition percentages→Percent Composition Calculator
Common mistakes to avoid
- •Forgetting to balance equations before stoichiometry. Unbalanced equations give wrong mole ratios.
- •Using molality when molarity is needed (or vice versa). Check units: mol/L vs mol/kg solvent.
- •Ignoring significant figures in concentration calculations—propagate precision appropriately.
- •Assuming Henderson-Hasselbalch works outside buffer range (±1 pH of pKa).
- •Confusing strong vs. weak acids: HCl dissociates 100%, but CH₃COOH requires Ka calculation.
- •Forgetting temperature effects on equilibrium constants and Kw (Kw changes with temperature).
- •Using wrong stoichiometric coefficients when converting between moles of different species.
- •Ignoring that volumes don't add perfectly for non-ideal mixtures (e.g., ethanol + water).
Editorial policy
- ✓All calculators provide educational estimates, not professional laboratory guidance.
- ✓Atomic weights and constants follow IUPAC standards. Sources are cited in each tool.
- ✓We don't store your data. All calculations run client-side in your browser.
- ✓Results are rounded for display but computed with full precision internally.
- ✓Found an error? Email us at hello@everydaybudd.com and we'll fix it promptly.
- ✓Tools are updated when IUPAC values or chemical education standards change.
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All Chemistry & Biochemistry Tools
Frequently Asked Questions
Are these chemistry calculators accurate for lab work?
Our calculators use standard chemical formulas and IUPAC conventions. They're accurate for educational purposes and lab preparation. For research-grade work, verify critical calculations and follow your institution's protocols.
Where do the molar mass values come from?
We use IUPAC standard atomic weights (2021 values). For elements with ranges (like lithium or hydrogen), we use conventional atomic weights. Results are accurate for typical lab calculations but may need adjustment for isotopically enriched samples.
How do I know which pH formula to use?
Strong acids/bases: use direct concentration calculations. Weak acids/bases: use Ka/Kb and Henderson-Hasselbalch. Our pH Calculator guides you based on the compound type and provides step-by-step explanations.
Can these calculators handle buffer preparation?
Yes, our Buffer Calculator computes ratios for target pH using Henderson-Hasselbalch. Enter your desired pH, pKa, and total concentration to get exact volumes/masses of acid and conjugate base needed.
Why do stoichiometry answers sometimes differ from my textbook?
Common causes: different atomic mass values (we use IUPAC 2021), rounding at different steps, or unbalanced equations. Our Stoichiometry Calculator shows balanced equations and step-by-step mole calculations for verification.
Do the calculators account for activity coefficients?
Most educational calculators assume ideal solutions (activity coefficients = 1). This works well for dilute solutions. For concentrated electrolytes, real solution behavior deviates. We note these limitations in relevant calculators.