Question

What is the number of elements in :
1. 1st period and
2. 2nd period of modern periodic table.

Answer 1

Explanation:

Elements 95 to 118 have only been synthesized in laboratories or nuclear reactors.

Answer 2

Answer:

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.