early periodic table
- Created by: siobhan
- Created on: 18-05-13 09:44
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- The modern periodic table
- During the 19th century, many elements had been discovered but scientists did not know about the structure of atoms.
- Scientists tried to find ways to classify the elements based on their properties and atomic weight
- In 1863 Newlands proposed his law of octaves, which stated that similar properties are repeated every eight element. He put the 62 elements known at the time into 7 groups according to atomic weight. After calcium the properties did not match very well within the groups so other scientists id not accept his ideas
- In 1869 Mendeleev produced a better table. He left gaps for undiscovered elements meaning the groups of known elements did have similar properties. He predicted the properties of the missing elements. As some of these elements were dicovered, Mendeleev's predictions were true and other scientists accepted his ideas.
- Mendeleev's table became the basis for the modern periodic table.
- During the 19th century, many elements had been discovered but scientists did not know about the structure of atoms.
- In 1863 Newlands proposed his law of octaves, which stated that similar properties are repeated every eight element. He put the 62 elements known at the time into 7 groups according to atomic weight. After calcium the properties did not match very well within the groups so other scientists id not accept his ideas
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