Question

How did Dmitri Mendeleev arrange the periodic law?

a. Each set of elements was arranged in special columns based on their mass.
b. Each set of elements was arranged in special columns based on their diameter.
c. Each set of elements was arranged in special periods based on their qualities.
d. Each set of elements was arranged in alphabetical order.

Answer 1

a. Each set of elements was arranged in special coloumns based on their mass.