Question

Which element has the smallest atomic radius? calcium potassium scandium titanium

Answer 1

 The element  that has the smallest  atomic radius is  titanium

          explanation

• Calcium,potassium,  scandium and titanium are in  period  4 in the periodic table.

• Generally  the atomic   radius    decreases  across the period (from the left to the right) .  This is because  across the period  there is increase  in nuclear charge  which  make electrons been strongly attracted to the nuclear.

• Titanium is in atomic number 22 thus it has  more nuclear  charge  that  calcium,potassium and  scandium therefore  titanium has the  smallest atomic radius.

Answer 2

Answer: Option (d) is the correct answer.

Explanation:

It is known that in a periodic table, atomic size decreases when we move from left to right.

The given elements potassium, calcium, scandium, and titanium all belongs to  third period.

Therefore, out of these elements potassium is at the extreme left and titanium is towards the right. Thus, we can conclude that titanium is the element which has the smallest atomic radius.