Question

How many elements are present in 3rd period of the modern periodic table?

• A. 32
• B. 8
• C. 18
• D. 2

Answer 1

The Correct Option is B

Correct answer: 8
 
Explanation:
The 3rd period of the modern periodic table contains 8 elements. These elements are from s-block and p-block, with the electron filling in the 3s and 3p orbitals. 

The elements in the 3rd period are:
Sodium (Na), Magnesium (Mg), Aluminium (Al), Silicon (Si), Phosphorus (P), Sulfur (S), Chlorine (Cl), and Argon (Ar) 

So, the number of elements in the 3rd period is 8.