Question

1. check the box if the statement describes the law of octaves or the law of triads.

it was created by johann dôbereiner during early developments of the periodic table.
this theory did not work for group 2 elements.
the math did not work for all groups of elements.
every eighth element has similar physical and chemical properties.

1. choose the best answer.

what was discussed at the karlsruhe congress?
what are the rules for naming an element?
what is the best way to rotate elements using atomic mass?
how should the chemical properties of an element be represented?
how should the number of protons in an element be measured?

Explanation:

• Law of Triads: Johann Döbereiner created it. He grouped elements into triads where the middle - element had properties (including atomic mass) that were an average of the other two.
• Law of Octaves: John Newlands proposed that every eighth element (when arranged in order of increasing atomic mass) had similar physical and chemical properties. However, it had limitations. For example, it did not work well for heavier elements (not just group 2).
• Karlsruhe Congress: The main outcome was the agreement on the rules for naming elements.

Answer:

1.

• "It was created by Johann Döbereiner during early developments of the periodic table": Law of Triads
• "This theory did not work for group 2 elements": Law of Octaves
• "The math did not work for all groups of elements": Law of Octaves
• "Every eighth element has similar physical and chemical properties": Law of Octaves

1. What are the rules for naming an element?