Chapter 9, Problem 4STP

Interpretation Introduction

Interpretation:

The pattern displayed by elements in the periodic table needs to be identified.

Concept introduction:

According to periodic law, there is repetition of chemical and physical characteristics of the elements takes place when they are put in increasing order of the atomic number.

Answer to Problem 4STP

Option C is correct.

Explanation of Solution

Reason for correct option:

Atomic number increases from top to bottom and left to right in a group and period respectively. So, the properties of elements are repeated when they are arranged in increasing atomic number.

Conclusion

Reason for incorrect option:

Option A is not correct as atomic radius increases top to bottom in a group and decreases across the period.

Option B and D are quietly right as the atomic mass and number are not similar. Atomic number represents proton number while atomic mass is the total number of proton and neutron. An atom of one element could a have lower atomic number but it contain possibly high atomic mass. Therefore, these two options are not correct.