Combustion Analysis & Empirical Formula Calculator

Elemental Analysis of Organic Compounds

Enter the sample mass and the masses of CO₂ and H₂O produced during combustion. Optionally, include N₂, SO₂, and the molar mass for advanced analysis.

Examples

See how combustion analysis works with real compounds.

Glucose (C₆H₁₂O₆)

Organic Compound

A 1.00 g sample of glucose produces 1.47 g CO₂ and 0.60 g H₂O upon combustion.

Sample Mass (g): 1 g

CO₂ Produced (g): 1.47 g

H₂O Produced (g): 0.6 g

N₂ Produced (g): g

SO₂ Produced (g): g

Molar Mass (g/mol): 180.16 g/mol

Ethanol (C₂H₆O)

Organic Compound

A 0.500 g sample of ethanol yields 0.967 g CO₂ and 0.593 g H₂O.

Sample Mass (g): 0.5 g

CO₂ Produced (g): 0.967 g

H₂O Produced (g): 0.593 g

N₂ Produced (g): g

SO₂ Produced (g): g

Molar Mass (g/mol): 46.07 g/mol

Urea (CH₄N₂O)

Organic Compound

A 1.00 g sample of urea produces 0.733 g CO₂, 0.294 g H₂O, and 0.467 g N₂.

Sample Mass (g): 1 g

CO₂ Produced (g): 0.733 g

H₂O Produced (g): 0.294 g

N₂ Produced (g): 0.467 g

SO₂ Produced (g): g

Molar Mass (g/mol): 60.06 g/mol

Thiophene (C₄H₄S)

Organic Compound

A 0.800 g sample of thiophene yields 1.47 g CO₂, 0.300 g H₂O, and 0.320 g SO₂.

Sample Mass (g): 0.8 g

CO₂ Produced (g): 1.47 g

H₂O Produced (g): 0.3 g

N₂ Produced (g): g

SO₂ Produced (g): 0.32 g

Molar Mass (g/mol): 84.14 g/mol

Other Titles
Understanding Combustion Analysis: A Comprehensive Guide
Mastering Empirical and Molecular Formula Determination

What is Combustion Analysis?

  • Definition and Purpose
  • Historical Context
  • Modern Applications
Combustion analysis is a fundamental technique in analytical chemistry used to determine the elemental composition of organic compounds. By burning a known mass of a compound and measuring the masses of the products (CO₂, H₂O, etc.), chemists can deduce the amounts of carbon, hydrogen, and other elements present.
Why is Combustion Analysis Important?

Practical Uses

  • Determining the formula of an unknown organic compound.
  • Quality control in pharmaceuticals and food industry.

Step-by-Step Guide to Using the Calculator

  • Input Requirements
  • Calculation Process
  • Interpreting Results
To use the calculator, enter the sample mass and the masses of CO₂ and H₂O produced. Optionally, provide N₂, SO₂, and the molar mass for advanced analysis. The calculator will compute the mass and percent composition of each element, and determine the empirical and molecular formulas.
How to Enter Data Correctly

Step-by-Step Examples

  • Inputting data for glucose combustion.
  • Calculating empirical formula for an unknown sample.

Real-World Applications of Combustion Analysis

  • Organic Chemistry Research
  • Industrial Quality Control
  • Environmental Monitoring
Combustion analysis is widely used in research labs, industry, and environmental science. It helps identify unknown compounds, verify product purity, and monitor pollutants.
Industries Benefiting from Combustion Analysis

Industry Examples

  • Testing fuel composition in energy sector.
  • Analyzing food additives for regulatory compliance.

Common Misconceptions and Correct Methods

  • Pitfalls in Data Entry
  • Misinterpretation of Results
  • Best Practices
A common mistake is neglecting to account for all elements or entering incorrect masses. Always double-check input values and ensure units are consistent. The calculator provides validation and error messages to guide users.
Avoiding Calculation Errors

Common Mistakes

  • Entering CO₂ mass in mg instead of g.
  • Forgetting to include N₂ or SO₂ for nitrogen/sulfur analysis.

Mathematical Derivation and Examples

  • Stoichiometric Calculations
  • Empirical Formula Determination
  • Molecular Formula Calculation
The calculator uses stoichiometric relationships: C is determined from CO₂ (1 mol CO₂ = 1 mol C), H from H₂O (1 mol H₂O = 2 mol H), N from N₂, S from SO₂. Oxygen is found by difference. Empirical formula is calculated by dividing each element's mole count by the smallest value, then rounding to the nearest whole number.
Worked Example: Glucose

Calculation Examples

  • 1.00 g glucose → 1.47 g CO₂, 0.60 g H₂O → C₆H₁₂O₆
  • 0.500 g ethanol → 0.967 g CO₂, 0.593 g H₂O → C₂H₆O