Chapter 15, Problem 10RAT

To determine

The correct option for the statement “Strontium, Sr (number 38), is especially dangerous of humans because it tends to accumulate in calcium-rich bone marrow tissues (calcium, Ca, number 20). This fact relates to the organisation of the periodic table in that strontium and calcium are both”.

Answer to Problem 10RAT

The correct option for the statement “Strontium, Sr (number 38), is especially dangerous of humans because it tends to accumulate in calcium-rich bone marrow tissues (calcium, Ca, number 20). This fact relates to the organisation of the periodic table in that strontium and calcium are both” is option (b).

Explanation of Solution

Calcium is readily found in the body and is absorbed by the bones. The atomic number of calcium is $20$ and the atomic number of strontium is $38$.

The electron configuration of calcium is $1s^2,2s^{2}2p^6,3s^{2}3p^6,4s^2$. It means calcium is present in fourth row and second group of periodic table. The electron configuration of strontium is $1s^2,2s^{2}2p^6,3s^{2}3p^6,4s^{2}3d^{10}4p^6,5s$. It means strontium is present in fifth row and second group of periodic table.

From the electronic configuration of both elements, it is clear that they are present in same vertical column or same group. Thus, they are similar in chemical and physical properties. So it is hard for the human body to differentiate between two, and hence, the body used to absorb strontium being calcium.

Conclusion:

Therefore, the correct option for the statement “Strontium, Sr (number 38), is especially dangerous of humans because it tends to accumulate in calcium-rich bone marrow tissues (calcium, Ca, number 20). This fact relates to the organisation of the periodic table in that strontium and calcium are both” is option (b).