Question

1. the modern periodic table has_____periods ​

Answer 1

Answer:

Seven

A period is a horizontal row of the periodic table. There are seven periods in the periodic table, with each one beginning at the far left. A new period begins when a new principal energy level begins filling with electrons. Period 1 has only two elements (hydrogen and helium), while periods 2 and 3 have 8 elements.

Explanation:

Hope this answer helps you!

Answer 2

Answer:

modern periodic table has 7 periods