Chapter AS, Problem 1PQ

Interpretation Introduction

Interpretation:

The particles that are present in equal numbers in neutral atoms has to be identified.

Concept Introduction:

An atom is considered to be simplest unit of any matter that makes up an element. It is further composed of 3 subatomic particles: electrons, protons, neutrons.

Negatively charged species are electrons, positively charged species are protons and neutral species are neutrons. Number of protons or electrons comprise atomic number of element whereas sum of protons and neutrons comprise atomic mass of an element.

Answer to Problem 1PQ

Option (D) is the correct one.

Explanation of Solution

Reason for correct option:

Any neutral atom contains equal number of protons and electrons. Example, carbon atom, the electronic configuration is $1s^{1}2s^{2}2p^2$ with atomic number 6. So there are 6 electrons and 6 protons that make it a neutral species. To maintain electro-neutrality of species electrons and protons are equal.

Hence, correct option is (D).

Reason for incorrect option:

For electro-neutrality of species, electron and protons are equal in count as electrons possess unit negative charge and protons possess unit positive charge.

Therefore option (A), (B) and (C) are incorrect.

Conclusion

In all neutral atoms, equal number of protons and electrons are present. So the correct option is (D).