Chapter 7, Problem 99A

Interpretation Introduction

Interpretation:

The valence electrons for atoms of oxygen, sulfur, arsenic, phosphorus, bromine.

Concept introduction:

The electronic configuration of different elements is defined by arranging the electrons in different energy levels. There is a standard format for filling up electrons in the sub shells. The electronic configuration is written using principal quantum number, n. Each energy level is identified using s, p, d, f and number of electrons are written as superscript.

Answer to Problem 99A

The number of valence electrons of oxygen is 6, Sulphur is 6, Arsenic is 5, Phosphorus is 5, Bromine is 7.

Explanation of Solution

The atomic number of Oxygen is 8 and electronic configuration is depicted as ${\text{1s}}^2{\text{2s}}^2{\text{2p}}^4$. Hence, there are 6 valence electrons.

The atomic number of sulphur is 16 and electronic configuration is depicted as ${\text{1s}}^2{\text{2s}}^2{\text{2p}}^6{\text{3s}}^2{\text{3p}}^4$. Hence, there are 6 valence electrons.

The atomic number of Arsenic is 33 and electronic configuration is depicted as ${\text{1s}}^2{\text{2s}}^2{\text{2p}}^6{\text{3s}}^2{\text{3p}}^6{\text{3d}}^{10}{\text{4s}}^{2}4{\text{p}}^3$. Hence, there are 5 valence electrons.

The atomic number of Phosphorus is 15 and electronic configuration is depicted as ${\text{1s}}^2{\text{2s}}^2{\text{2p}}^6{\text{3s}}^2{\text{3p}}^5$. Hence, there are 5 valence electrons.

The atomic number of Bromine is 35 and electronic configuration is depicted as ${\text{1s}}^2{\text{2s}}^2{\text{2p}}^6{\text{3s}}^2{\text{3p}}^6{\text{3d}}^{10}{\text{4s}}^{2}4{\text{p}}^5$. Hence, there are 7 valence electrons.

Conclusion

The number of valence electrons of oxygen is 6, Sulphur is 6, Arsenic is 5, Phosphorus is 5, Bromine is 7.