Question

please guys answers these question all its urgent guys:​

Answer 1

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Answer 2

Answer:

Explanation:

1. b) 118

2.b)Law of octaves

3.a)Atomic number

1. Dobereiner tried to arrange the elements with similar properties,with groups of three (traids).He arranged in the order of increasing atomic masses.The atomic mass of the middle element was roughly the average of the atomic mass of other two elements.

2. Noble gases are placed in a separate group because the valence will be 0 and they don't react with oxygen and hydrogen.