Question

From the symbol $_{19}{K^{40}}$, state the atomic number of potassium.

Answer 1

Hint: We know that the central English alphabet is the chemical symbol of element and on top of chemical symbol we write its mass while the below represent its atomic number. So, by observing the value on down, we can tell the atomic number of K.

Complete answer:
We have studied the format of writing atomic symbols along with atomic number and mass number.
We know that the central English alphabet is the chemical symbol of element and on top of chemical symbol we write its mass while the below represent its atomic number.
So, if we see the element given to us; the element is ‘K’ meaning Potassium.
From the symbol, the below numerical value i.e. 19 states the atomic number of the element.

Therefore, the atomic number of the element is 19.

Additional information:
It belongs to s- block elements. It is an alkaline metal. Potassium is mineral. It acts as an electrolyte in the body. It helps nerves to function properly. During muscle contractions, there is exchange of potassium and other ions only. It even maintains the heart beat in the human body.

Note:
The atomic number is the number of protons or electrons present in a neutral atom of an element. There are many atoms that have atomic numbers but mass numbers are different. They are called isotopes. The common example of isotopes is hydrogen, deuterium and tritium. All these have atomic numbers which are equal to 1 while the mass number is 1, 2 and 3 respectively.