Question

Write the atomic number of the element present in the third period and seventeenth group of the periodic table.

Answer 1

This atom is cl and it's atomic number is 17

Answer 2

The atomic number of the element present in the third period and a seventeenth group of the periodic table -

There are two elements in the 1st period and 8 elements in the 2nd period.,

The 3rd period starts with the element with Z = 11(sodium).

So, there are 9 elements in the 3rd period. Thus, the 3rd period ends with the element with Z = 18(argon), i.e., the component of the 18th group of the 3rd period has Z = 18. Hence, the element in the 17th group of the 3rd period has atomic number Z = 17, chlorine(Cl) with atomic mass 35.453, which is a p block element.