John Dalton: Father of Modern Atomic Theory

John Dalton (1766–1844)

The Life and Scientific Contributions of the Father of Modern Atomic Theory

• Early Life and Education
• Meteorological Studies
• Dalton's Atomic Theory
• Research on Color Blindness
• Legacy and Scientific Impact

• Born September 6, 1766, in Eaglesfield, Cumberland, England.
• Came from a modest Quaker family; received limited formal schooling.
• Demonstrated early brilliance in mathematics and teaching.
• Began teaching at age 12; continued his own education through self-study and mentorship.
• Moved to Manchester in 1793, where he spent most of his professional life.

1787: Start of Observations Begins a lifelong daily record of meteorological observations. 1793: First Major Publication Publishes Meteorological Observations and Essays. 1803: Dalton's Law Develops the law of partial pressures of gases. 1808: Atomic Theory Proposed Publishes A New System of Chemical Philosophy, introducing the atomic theory. 1844: Death of John Dalton Passes away in Manchester after a series of strokes.

• All matter is composed of tiny, indivisible atoms.
• Atoms of the same element are identical in mass and properties.
• Atoms combine in simple, whole-number ratios to form compounds.
• Chemical reactions involve the rearrangement, separation, or combination of atoms—never their creation or destruction.
• Provided a quantitative basis for understanding chemical combinations, moving beyond alchemy.

> Every form of matter is composed of small particles, the ultimate particles of all homogeneous bodies are perfectly alike in weight, figure, etc.

— John Dalton

John Dalton's work remains the bedrock of modern chemical science.

Paving the way for 19th and 20th-century physics and chemistry.