Atomic Structure: Determining Protons, Electrons, and Neutrons in an Atom
In this article, we will explore how to determine the number of protons, electrons, and neutrons in an atom, specifically in the case of an atom with an atomic number of 12 and an atomic mass of 18.
Atomic Number (Z) and Mass Number (A)
The atomic number (Z) of an atom represents the number of protons present in the nucleus of an atom. It is a unique identifier for each element. The mass number (A) of an atom is the total number of protons and neutrons present in the nucleus.
In our example, the atomic number (Z) is 12, and the mass number (A) is 18.
**Protons (p+)
The number of protons in an atom is equal to the atomic number (Z). Therefore, the number of protons in our atom is:
p+ = 12
**Neutrons (n)
The number of neutrons in an atom can be calculated by subtracting the atomic number (Z) from the mass number (A). In our case:
n = A - Z = 18 - 12 = 6
So, the number of neutrons in our atom is 6.
**Electrons (e-)
The number of electrons in a neutral atom is equal to the number of protons. This is because the positive charge of the protons is balanced by the negative charge of the electrons. Therefore, the number of electrons in our atom is:
e- = p+ = 12
Summary
In summary, the atom with an atomic number of 12 and an atomic mass of 18 has:
- 12 protons (p+)
- 6 neutrons (n)
- 12 electrons (e-)
We hope this helps you understand how to determine the number of protons, electrons, and neutrons in an atom!
