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6 Cards in this Set
- Front
- Back
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Element |
An element contains all the same type of atoms |
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What did Dmitri Mendeleev do with the modern periodic table? |
Mendeleev arranged the element into groups (vertical) and periods (horizontal) based on their relative atomic masses and patterns in their properties. He left gaps for undiscovered elements and predicted properties of missing elements. When new elements were discovered, they fitted Mendeleev's predictions. |
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Relative Atomic Mass |
The relative atomic mass is a measure of the mass of one atom of the element. |
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Johann Döbereiner's Idea |
Döbereiner noticed triads that linked patterns of the relative atomic masses for three elements |
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John Newland's Idea |
Newlands noticed an octaves pattern where every eighth element had similar properties |
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Why did scientists reject the ideas of Döbereiner and Newlands? |
They rejected their ideas because most elements did not fit the patterns of octaves or triads |
