Biography on John Dalton

Essay by frankinsonHigh School, 11th gradeA, November 2006

download word file, 1 pages 3.7

Downloaded 22 times

John Dalton an English chemist and physicist, was known to us for his atomic theory. Born in 1766, September, and taught by his father. He started teaching people at the young age of 12, but since he was discontent with the wages he got, which was just about 5 shillings, he started farming for two years. Later, at 1793, he studied mathematics and natural philosophy at the Manchester Academy. At 1800, he published his atomic theory, explaining how and why elements would combine with one another in fixed ratios and sometimes also in multiples of those ratios.

Inside his theory, he stated the following main points:

1. Elements are made out of tiny particles called atoms

2. The atoms of each element are the same, having the same mass

3. Compounds have a fixed ratio of atoms, so they have a constant compositions

4. Atoms of each element are different, having different mass

5. Chemical reactions are just rearranging the combinations of the atoms, and atoms can not be destroyed

The theory that John Dalton stated have persuaded half of the scientists of that time, with oppositions dying off half a century later, since he added this to his theory:

When atoms combine in only one ratio, " must be presumed to be a binary one, unless some cause appear to the contrary". It was proved right later, but caused his theory to be unrecognised by some scientists.

Other contributions he gave us was his contribution on colour blindness. Since he was coloured-blinded himself, colour-blind was sometimes called Daltonism.

John Dalton died at Manchester of paralysis. He first suffered from it since 1837, when he got his first stroke. After finishing his last experiment, he was found dead felling off his bed, by his assistant. A sculpture of his...