Chapter 6, Problem 55A

Interpretation Introduction

Interpretation:

To determine the atomic radius of the Indium atom.

Concept Introduction :

The periodic table is a columnar structure that organizes different elements into groups based on how they behave. The elements in the periodic table of today are ordered according to the periodic law. The elements are organized in the modern periodic table in increasing order of their atomic number. Periodic trends are patterns found in the periodic table that show several facets of a particular element. A periodic trend is observed in atomic size also.

Answer to Problem 55A

Slightly less than 150

Explanation of Solution

Across the period, the atomic radius decreases. This is because when moving left to right in the periodic table, the number of shells stays constant while the nuclear charge increases by one at each step. As nuclear charge increases, electrons in the outermost shell are drawn to it with increasing force, which causes the size of atoms to gradually shrink over the period.

Indium is present right next to cadmium. The size of cadmium is 150 pm. As atomic size decreases from list to right, thus, the atomic size of indium will be slightly less than 150 pm

Conclusion

The periodic trend helps in estimating various properties of elements.