VerChem is a free, professional-grade chemistry platform offering 8 chemistry calculators, 3 environmental engineering tools, an interactive periodic table with all 118 elements (NIST/IUPAC certified), and a database of 1,000+ compounds. Built for students, chemists, and engineers.

Is VerChem free to use?

Yes! All VerChem features are completely free for AIVerID members. We follow a "Free First" strategy to make world-class chemistry tools accessible to everyone worldwide.

How accurate is VerChem data?

VerChem uses NIST (National Institute of Standards and Technology) and IUPAC (International Union of Pure and Applied Chemistry) as authoritative data sources. All 118 elements have certified atomic masses and properties updated to 2021 standards.

What calculators does VerChem offer?

VerChem offers 8 chemistry calculators: Molar Mass, Equation Balancer, Stoichiometry (8 modes), pH Calculator (7 modes), Gas Laws (9 modes including Van der Waals), Thermodynamics, Chemical Kinetics, and Electrochemistry. Plus 3 environmental tools: Water Quality, Air Quality, and Soil Quality.

How do I calculate molar mass?

Enter a chemical formula (e.g., H2SO4, NaCl, C6H12O6) into the Molar Mass Calculator. It automatically calculates molecular weight by summing atomic masses × subscripts. For H2O: (2 × 1.008) + (1 × 15.999) = 18.015 g/mol. Uses NIST atomic masses.

What is the Ideal Gas Law formula?

The Ideal Gas Law is PV = nRT, where P = pressure, V = volume, n = moles of gas, R = gas constant (8.314 J/mol·K or 0.0821 L·atm/mol·K), and T = temperature in Kelvin. VerChem Gas Laws Calculator supports 9 modes including Combined Gas Law and Van der Waals equation.

How do I calculate pH from concentration?

pH = -log[H+]. For a 0.01 M HCl solution: pH = -log(0.01) = 2. For bases, calculate pOH first, then pH = 14 - pOH. VerChem pH Calculator handles strong/weak acids and bases, buffer solutions, and shows visual pH scale.

What is BOD and COD in water quality?

BOD (Biochemical Oxygen Demand) measures oxygen consumed by microorganisms decomposing organic matter over 5 days at 20°C. COD (Chemical Oxygen Demand) measures total oxygen needed to chemically oxidize all organic matter. BOD/COD ratio indicates biodegradability: 0.6 = highly biodegradable.

What are Thai water quality standards?

Thai PCD (Pollution Control Department) standards: Type ก (Industrial): BOD ≤20, COD ≤120, SS ≤50 mg/L. Type ข (Relaxed Industrial): BOD ≤60, COD ≤400, SS ≤150 mg/L. Type ค (Community): BOD ≤40, COD ≤200, SS ≤70 mg/L. VerChem Water Quality Calculator includes Thai standards compliance checker.

How many elements are in the periodic table?

There are 118 confirmed elements. Elements 1-94 occur naturally (though some like Technetium and Promethium are extremely rare). Elements 95-118 are synthetic, created in laboratories. The latest additions (Nihonium, Moscovium, Tennessine, Oganesson) were confirmed by IUPAC in 2016.

What are rare earth elements?

Rare earth elements include 17 elements: Scandium (Sc), Yttrium (Y), and the 15 Lanthanides (La-Lu: Lanthanum, Cerium, Praseodymium, Neodymium, Promethium, Samarium, Europium, Gadolinium, Terbium, Dysprosium, Holmium, Erbium, Thulium, Ytterbium, Lutetium). Despite the name, most are not rare but are difficult to separate from each other.

What is a limiting reagent?

A limiting reagent is the reactant that is completely consumed first in a chemical reaction, determining the maximum amount of product that can be formed. VerChem Stoichiometry Calculator identifies the limiting reagent and calculates theoretical yield, actual yield, and percent yield.

How do I convert moles to grams?

Mass (g) = Moles × Molar Mass (g/mol). For example, 2 moles of water: 2 mol × 18.015 g/mol = 36.03 g. To convert grams to moles, divide: Moles = Mass / Molar Mass.

How do you balance a chemical equation?

To balance a chemical equation: 1) Write the unbalanced equation, 2) Count atoms of each element on both sides, 3) Add coefficients to balance atoms, starting with the most complex molecule, 4) Verify all atoms are balanced.

Why must chemical equations be balanced?

Chemical equations must be balanced to satisfy the Law of Conservation of Mass, which states that matter cannot be created or destroyed. The number of atoms of each element must be the same on both sides of the equation.

⚡Free Online Tool • No Sign-up Required

Chemical Equation
Balancer

Balance any chemical equation instantly. Perfect for students, teachers, and chemists. 100% free, unlimited use.

Enter Your Chemical Equation

Press Enter ↵

Try These Examples

Click any equation below to balance it instantly

How to Balance Chemical Equations

Our advanced algorithm uses matrix algebra and Gaussian elimination to balance any chemical equation in milliseconds

📝

Step 1

Enter Equation

Type your unbalanced chemical equation using standard notation (e.g., H2 + O2 -> H2O)

🔍

Step 2

Parse & Analyze

Our system identifies all elements and counts atoms on both sides of the equation

⚡

Step 3

Calculate Coefficients

Advanced algorithms find the smallest whole number coefficients that balance the equation

✅

Step 4

Verify & Display

We verify atom counts match and show you the balanced equation with detailed breakdown

Types of Chemical Reactions

Our balancer automatically identifies and labels reaction types

Synthesis

A + B → AB

Two substances combine to form one product

Decomposition

AB → A + B

One compound breaks into simpler substances

Combustion

CₓHᵧ + O₂ → CO₂ + H₂O

Rapid reaction with oxygen producing heat

Redox

Oxidation + Reduction

Electron transfer between species

Why Choose VerChem Equation Balancer?

🚀

Lightning Fast

Balance equations in milliseconds using advanced algorithms

🎯

100% Accurate

Verified against IUPAC standards with atom count verification

📱

Works Everywhere

Use on any device - desktop, tablet, or mobile

🆓

Completely Free

No sign-up, no limits, no hidden costs. Forever free!

🧪

All Reaction Types

Handles synthesis, combustion, redox, and complex reactions

📚

Educational

Shows step-by-step breakdown for learning

Frequently Asked Questions

How do I balance a chemical equation?+

Simply enter your unbalanced equation using the format "Reactants -> Products" (e.g., H2 + O2 -> H2O). Use element symbols with subscripts as numbers (H2O, not H₂O). Our calculator will instantly provide the balanced equation with correct coefficients.

What is a balanced chemical equation?+

A balanced chemical equation has equal numbers of each type of atom on both sides of the reaction arrow. This follows the Law of Conservation of Mass - matter cannot be created or destroyed in a chemical reaction.

Can this balance complex redox equations?+

Yes! Our advanced algorithm can handle complex redox equations including those involving permanganate (MnO4⁻), dichromate (Cr2O7²⁻), and other challenging species. We support coefficients up to 20.

Is this calculator free to use?+

Absolutely! VerChem Equation Balancer is 100% free with no usage limits. No sign-up required. Use it as many times as you need for homework, exams, or research.

How accurate is this equation balancer?+

Our balancer uses matrix algebra (Gaussian elimination) combined with optimized search algorithms. Every result includes atom count verification to ensure 100% accuracy.

Ready to Balance More Equations?

Explore our complete suite of chemistry calculators

Stoichiometry Calculator →Periodic Table →

Loading VerChem

Preparing your chemistry tools...

Try These Examples

Click any equation below to balance it instantly

How to Balance Chemical Equations

Our advanced algorithm uses matrix algebra and Gaussian elimination to balance any chemical equation in milliseconds

📝

Step 1

Enter Equation

Type your unbalanced chemical equation using standard notation (e.g., H2 + O2 -> H2O)

🔍

Step 2

Parse & Analyze

Our system identifies all elements and counts atoms on both sides of the equation

⚡

Step 3

Calculate Coefficients

Advanced algorithms find the smallest whole number coefficients that balance the equation

✅

Step 4

Verify & Display

We verify atom counts match and show you the balanced equation with detailed breakdown

Types of Chemical Reactions

Our balancer automatically identifies and labels reaction types

Synthesis

A + B → AB

Two substances combine to form one product

Decomposition

AB → A + B

One compound breaks into simpler substances

Combustion

CₓHᵧ + O₂ → CO₂ + H₂O

Rapid reaction with oxygen producing heat

Redox

Oxidation + Reduction

Electron transfer between species

Why Choose VerChem Equation Balancer?

🚀

Lightning Fast

Balance equations in milliseconds using advanced algorithms

🎯

100% Accurate

Verified against IUPAC standards with atom count verification

📱

Works Everywhere

Use on any device - desktop, tablet, or mobile

🆓

Completely Free

No sign-up, no limits, no hidden costs. Forever free!

🧪

All Reaction Types

Handles synthesis, combustion, redox, and complex reactions

📚

Educational

Shows step-by-step breakdown for learning

Frequently Asked Questions

How do I balance a chemical equation?+

What is a balanced chemical equation?+

Can this balance complex redox equations?+

Is this calculator free to use?+

Absolutely! VerChem Equation Balancer is 100% free with no usage limits. No sign-up required. Use it as many times as you need for homework, exams, or research.

How accurate is this equation balancer?+

Our balancer uses matrix algebra (Gaussian elimination) combined with optimized search algorithms. Every result includes atom count verification to ensure 100% accuracy.

Chemical EquationBalancer

Try These Examples

How to Balance Chemical Equations

Enter Equation

Parse & Analyze

Calculate Coefficients

Verify & Display

Types of Chemical Reactions

Synthesis

Decomposition

Combustion

Redox

Why Choose VerChem Equation Balancer?

Lightning Fast

100% Accurate

Works Everywhere

Completely Free

All Reaction Types

Educational

Frequently Asked Questions

Ready to Balance More Equations?

Loading VerChem

Chemical EquationBalancer

Try These Examples

How to Balance Chemical Equations

Enter Equation

Parse & Analyze

Calculate Coefficients

Verify & Display

Types of Chemical Reactions

Synthesis

Decomposition

Combustion

Redox

Why Choose VerChem Equation Balancer?

Lightning Fast

100% Accurate

Works Everywhere

Completely Free

All Reaction Types

Educational

Frequently Asked Questions

Ready to Balance More Equations?

Chemical Equation
Balancer

Chemical Equation
Balancer