John dalton's main achievements

1, the establishment of atomism. 1803 inherited the naive atomism of ancient Greece and Newton's particle theory, and put forward atomism. The relative comparison method is proposed to calculate the atomic weight of each element, and the first atomic scale is published.

2. Dalton put forward a systematic theory of chemical atoms, introduced atoms and atomic weights, and made a pioneering contribution to the volumetric analysis method.

Dalton suggested using simple symbols to represent the composition of elements and compounds.

Dalton was the first scientist to discover the phenomenon of color blindness.

The key points of atomism put forward by Dalton;

1. Chemical elements are composed of inseparable particles-atoms. He believes that the atom is the smallest unit that can not be separated in all chemical changes.

2. The atomic properties and mass of the same element are the same, but the atomic properties and mass of different elements are different. Atomic weight is one of the basic characteristics of elements.

3. When different elements are combined, atoms are combined in a simple integer ratio. The law of multiple is deduced and proved by experiments. If the mass of one element is fixed, the mass of another element in various compounds must be a simple integer ratio.

Classification of Dalton's disease:

Congenital color vision disorder is usually called color blindness, which can't distinguish various colors or a certain color in the natural spectrum. And those with poor color discrimination are called weak colors. Color blindness can be divided into color blindness and partial color blindness (red blindness, green blindness, blue-yellow blindness, etc. ). Color weakness includes full color weakness and partial color weakness (red weakness, green weakness, blue yellow weakness, etc. ).

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