Question

Which of the following groups of three elements each constitutes Dobereiner's triads?

• A. Ca, Ba, F
• B. Li, Mg, Al
• C. Cl, H, Si
• D. Cl, Br, I

Answer 1

Answer:

D. Cl, Br, I

• The correct Dobereiner's triad is Cl, Br, I.

• Johann Wolfgang Dobereiner, a German scientist, discovered Dobereiner's triads, which are collections of elements with related properties.

• He noticed that triads-groups of three elements-could develop in which all the components had comparable physical and chemical characteristics.

• According to Dobereiner's law of triads, the atomic masses of the first and third elements in a triad will approximately equal the atomic masses of the second element in that triad.