To determine the number of neutrons in an atom of potassium (K), one must first understand the structure of an atom. An atom is composed of protons, neutrons, and electrons. The number of protons is equal to the atomic number of the element, which is unique to each element and can be found on the periodic table. The number of neutrons, however, can vary because atoms of the same element can have different isotopes. Isotopes are atoms with the same number of protons but different numbers of neutrons.
To determine the number of neutrons in an atom of potassium (K), one must first understand the structure of an atom. An atom is composed of protons, neutrons, and electrons. The number of protons is equal to the atomic number of the element, which is unique to each element and can be found on the periodic table. The number of neutrons, however, can vary because atoms of the same element can have different isotopes. Isotopes are atoms with the same number of protons but different numbers of neutrons.
Here is a step-by-step guide to finding the number of neutrons in potassium:
1. Locate Potassium on the Periodic Table:
Potassium is represented by the symbol 'K' on the periodic table. Find potassium to gather the necessary information about its atomic structure.
2. Identify the Atomic Number:
The atomic number of potassium is 19. This number represents the number of protons in the nucleus of a potassium atom.
3. Find the Atomic Mass (Average Atomic Weight):
The atomic mass of potassium is approximately 39.0983 atomic mass units (amu). This value is the weighted average of all the naturally occurring isotopes of potassium.
4. Calculate the Number of Neutrons:
The number of neutrons in an atom is calculated by subtracting the atomic number from the atomic mass (rounded to the nearest whole number). This is because the atomic mass is roughly the sum of the number of protons and neutrons, as the mass of electrons is negligible.
Here's the calculation for potassium:
- Round the atomic mass to the nearest whole number: 39 amu (since 39.0983 is closer to 39 than to 40).
- Subtract the atomic number from the rounded atomic mass: 39 (rounded atomic mass) - 19 (atomic number) = 20.
Therefore, the most common isotope of potassium has 20 neutrons.
It's important to note that this calculation gives you the number of neutrons in the most abundant isotope of potassium. Potassium has several isotopes with different numbers of neutrons, but the isotope with 20 neutrons, potassium-39 (with an atomic mass of 39), is the most abundant, making up about 93.26% of all natural potassium. Other isotopes of potassium include potassium-40 and potassium-41, with 21 and 22 neutrons, respectively.