How many electrons will be found in the nucleus of an atom with mass number 23 and 17 neutrons?

Analysis

To solve this, we need to understand the structure of an atom and the subatomic particles that reside within it.

Concept Explanation

An atom consists of two main regions:

1. The Nucleus: Located at the center of the atom, it contains protons and neutrons. These are collectively known as nucleons.
2. The Extra-nuclear region: This is the space surrounding the nucleus where electrons orbit in shells or energy levels.

The mass number ($A$) of an atom is defined as the sum of its protons ($Z$) and neutrons ($N$):

Crucially, electrons are never found inside the nucleus. They are negatively charged particles that exist outside the nucleus.

Step-by-Step Solution

1. Identify the components: • Mass number ($A$) = 23 • Number of neutrons ($N$) = 17 • Number of protons ($Z$) = $A - N = 23 - 17 = 6$
2. Locate the particles: • The 6 protons and 17 neutrons are located inside the nucleus. • The electrons (which would be 6 in a neutral atom) are located in the shells outside the nucleus.
3. Conclusion: Since electrons are not part of the nuclear structure, the number of electrons found in the nucleus is zero.

Exam Tip

Always remember the "Nucleus Rule": The nucleus is the home of Protons and Neutrons only. If a question asks for the number of electrons in the nucleus, the answer is always "none" or "zero," regardless of the mass number or atomic number provided. Don't let the numbers distract you!