Question

Why are there only two elements in the first period of the periodic table? (1 point)

A. Because only two electrons can fit in the first orbit around the nucleus, and each period on the table is organized by number of orbits

B. Because the first two elements both start with H and are grouped together

C. Because the next elements have other things in common and they need to be arranged together

D. Because each row increases in atomic mass by a specific number so anything over five is in the second​

Answer 1

Answer:

A

Explanation:

Only 2 electrons can fit in the fist orbit around the nucleus is what placed them in the first row of the periodic table

Answer 2

Answer:A. Because only two electrons can fit in the first orbit around the nucleus, and each period on the table is organized by number of orbits

Explanation: This is because the The periodic table of elements is designed according to the number of shells from up going down together with  their increasing number of atomic numbers, Now only Hydrogen and Helium have one shell and are therefore the only two elements that should be placed in the first period .

Also note that in filling of their s-orbital, the maximum number of electrons that it can contain is 2 as in 1s²

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