The correct symbol for the isotope of potassium with 22 neutrons is __.
The Correct Answer and Explanation is:
The correct symbol for the isotope of potassium with 22 neutrons is K-39.
Explanation:
To understand why K-39 is the correct symbol, we first need to break down the components of an isotope.
- Isotopes are variants of elements that have the same number of protons but different numbers of neutrons. The number of protons in an atom determines the element, and the total number of protons and neutrons gives the atom’s mass number.
- Potassium (K) has an atomic number of 19, which means it has 19 protons in its nucleus. The number of protons defines the element as potassium. Since the atomic number is always the same for all isotopes of an element, potassium always has 19 protons, regardless of the isotope.
- The mass number of an isotope is the sum of protons and neutrons. If the isotope of potassium has 22 neutrons, we can calculate its mass number by adding the number of protons (19) and neutrons (22):
[
\text{Mass Number} = 19 \, (\text{protons}) + 22 \, (\text{neutrons}) = 41
]
So, this isotope of potassium has a mass number of 41. - The standard notation for isotopes is the symbol of the element followed by the mass number in superscript. The element symbol for potassium is K, and its mass number is 41, so the isotope is written as K-41.
However, it’s important to note that potassium typically exists in several isotopic forms, with K-39 being the most abundant isotope. This is because naturally occurring potassium consists primarily of potassium-39, which has 20 neutrons, not 22.
In conclusion, the correct symbol for the isotope of potassium with 22 neutrons is K-41.