Chapter 8, Problem 105A

Interpretation Introduction

Interpretation:

From the list below, the elements which are capable of forming molecules in which one of its atoms has an expanded octet need to be determined.

1. B b. C c. P d. O e. Se

Concept introduction:

In an expanded octet, the central atom has more than 8 electrons in the stable structure which includes bonding pairs and lone pairs.

Answer to Problem 105A

Phosphorus (P) and Selenium (Se) both are capable of forming molecules with expanded octet.

Explanation of Solution

Phosphorus belongs to period 3 and Selenium belongs to period 4 in the periodic table. For both the elements, d sub-shell is available. According to expanded octet rule, elements of period three or higher elements produce molecules with expanded octet atoms. Thus, phosphorus (P) and selenium (Se) both are capable of forming molecules with expanded octet.

Conclusion

Boron (B), carbon (C) and Oxygen (O) all are from period 2. Their d sub-shell is not available for bonding. Hence, B, C and O do not produce molecules with expanded octets.