Chemistry AI solver · Available now on Android

Balanced reactions, stoichiometry, and molar math, explained step by step.

Scan printed worksheets or handwritten chemistry problems on Android. Stemulus breaks down reaction balancing, mole conversions, limiting reactants, acid-base pH, and equilibrium calculations with numbered steps, verified arithmetic, and custom study guides.

iPhone, iPad, and Mac: coming soon to the App Store.

10 free scan credits to start. No sign-in needed.

Chemistry · Stoichiometry & Molarity

How many grams of NaOH (M = 40.00 g/mol) are required to neutralize 25.0 mL of 0.300 M H₂SO₄?

Step by step.

Write the balanced neutralization equation 2 NaOH + H₂SO₄ → Na₂SO₄ + 2 H₂O Sulfuric acid is diprotic (2 H⁺), requiring 2 mol NaOH per 1 mol H₂SO₄.
Calculate moles of H₂SO₄ and required moles of NaOH n(H₂SO₄) = 0.0250 L × 0.300 M = 0.00750 mol ⇒ n(NaOH) = 0.0150 mol Convert 25.0 mL to 0.0250 L and multiply by the 2 : 1 stoichiometric mole ratio.
Convert moles of NaOH to grams and verify m = 0.0150 mol × 40.00 g/mol = 0.600 g Check: (0.600 / 40.00) / 2 = 0.00750 mol acid neutralized.

Solution

m(NaOH) = 0.600 g

Arithmetic checks passed

Why use Stemulus for chemistry

Keep mole ratios, subscripts, and significant steps clear.

General and AP Chemistry problems combine conceptual reaction rules with multi-step unit conversions. A single flipped mole ratio throws off the entire calculation.

Explicit mole ratios and dimensional setup

Stemulus writes out the balanced chemical equation first, then shows each conversion factor (grams to moles, mole-to-mole ratio, and molarity or gas volume) step by step.

Arithmetic verification on quantitative problems

Supported stoichiometry, dilution, gas-law, and equilibrium calculations are checked by substituting the result back into the governing relation.

Enter your lab or homework calculation first

Record your own calculated value before tapping Check Problem so you can pinpoint where your conversion chain diverged without losing track of your attempt.

Copy clean LaTeX for chemistry lab reports

Export reaction equations, ICE table setups, and thermodynamic calculations directly as LaTeX for lab write-ups and study sheets.

Chemistry topics covered

General Chemistry, AP Chemistry, and introductory Organic.

Scan textbook exercises, lab pre-lab questions, or handwritten equations across core chemistry courses.

Reactions & Stoichiometry

Balancing Equations, Limiting Reactants & Yield

Chemical equation balancing, molar mass, empirical and molecular formulas, limiting reagents, percent yield, and net ionic equations.

Solutions, Acids & Equilibrium

Molarity, Titrations, pH, ICE Tables & Ksp

Dilution calculations, acid-base neutralization, strong and weak acid pH, buffer Henderson-Hasselbalch problems, equilibrium constants (Kc, Kp, Ksp), and Le Chatelier's principle.

Thermochemistry, Electrochem & Organic

Enthalpy, Gas Laws, Redox & Functional Groups

Ideal gas law (PV = nRT), calorimetry, Hess's law, Gibbs free energy, Nernst equation, oxidation states, rate laws, and introductory organic chemistry nomenclature and reaction types.

Prepare for chemistry exams

Turn your weekly chemistry problem sets into exam prep.

01 · Assignments

Group problems by chapter or lab unit

Save your stoichiometry, thermochemistry, or equilibrium problems into an assignment and tag the hardest ones Still stuck.
02 · Study guide

Generate a custom chemistry study guide

Build a study guide from your saved chemistry problems summarizing core formulas, reaction rules, worked examples from your homework, and what to review next.
03 · Practice

Run a three-question chemistry practice round

Practice three new questions generated from your assignment with progressive hints that help you set up the mole ratio or ICE table before revealing the answer.
04 · Offline

Review reactions and study guides offline for free

All saved chemistry solutions, study guides, and practice rounds stay on your Android device and open offline without using any credits.

How to check chemistry homework without burning online submission attempts

Whether you are working on pre-lab stoichiometry calculations or online general chemistry problem sets (like ALEKS, Mastering Chemistry, or WebAssign), small rounding or unit slips cost points:

Keep unrounded intermediate values through Step 02: Compare your intermediate molar quantities against Step 01 and Step 02 in Stemulus before rounding your final answer.
Verify your acid-base or redox stoichiometry: Many missed molarity problems come from overlooking a 2:1 or 3:1 proton or electron ratio in the balanced equation.
Generate a practice round before the quiz: After finishing your homework assignment, use the STEM Study Guide & Practice Generator to test yourself on three fresh stoichiometry or equilibrium problems with progressive hints. Taking Physics or Calculus too? Check out our Physics Solver App and Word Problem & Calculus Solver.

Pricing

Start free, then pay the way you study.

No sign-in is needed to check problems or subscribe. Every new account starts with 10 free scan credits. Link an Apple or Google account when you want to use your access on other platforms.

Subscription

Stemulus Pro

$4.99 per week

100 problem checks or study generations per rolling seven days
Each check becomes available again seven days after you use it
A failed generation returns its allowance
Renews weekly until canceled

One-time purchase

50 Scan Credits

$2.99 once

One credit checks one problem
No subscription, buy another pack when you need it
Opening saved solutions, guides and practice never uses a credit

US prices shown; your local price appears in the App Store or Google Play before you buy. A problem check uses one scan credit. For people without a subscription, generating a study guide or practice set also uses one scan credit, disclosed before you confirm, and a failed generation returns it. The subscription renews automatically until canceled; manage or cancel it in your App Store account or in Google Play. No free trial is offered.

Questions & Answers

Frequently asked questions

Can Stemulus balance chemical equations and solve stoichiometry from a photo?

Yes. Point your Android camera at a printed or handwritten chemical reaction or stoichiometry word problem, preview the crop before spending a credit, and get a numbered step-by-step breakdown.

Does the chemistry solver check its math?

Yes, for supported quantitative calculations, Stemulus runs an arithmetic verification check by substituting the final value back into the governing equation. Every solution also clearly discloses that AI-generated work can contain mistakes and tells you to review the result if a check cannot confirm it.

How much does the chemistry solver app cost?

You start with 10 free scan credits on Android with no sign-in required. After that, you can buy a one-time pack of 50 Scan Credits for $2.99 (no subscription) or subscribe to Stemulus Pro for $4.99/week.

Available now on Android. Coming to iPhone, iPad, and Mac.

Stemulus requires Android 8.0 or later, or iOS 26.5, iPadOS 26.5, or macOS 26.5 or later, and is available in English.