Question

How many neutrons are found in one atom of `""^36Cl`?

Answer 1

The number of neutrons in an atom of `""^36"Cl"` is `19`.

Explanation:

The symbol `""^36"Cl"` is the nuclear notation for chlorine-36, which is the mass number, `color(red)("A")`, for this particular chlorine isotope. The mass number is the sum of the protons and neutrons in the atomic nuclei of an isotope.

`color(red)("Z")+color(purple)("N")=color(blue)("A")`

You can determine the number of protons in a chlorine atom by looking it up on the periodic table, where you will see that its atomic number, `color(red)("Z")`, is `17`.

The number of neutrons, `color(purple)("N")`, in an isotope of an element is the difference between the mass number and atomic number.

`color(blue)("A")-color(red)("Z")=color(purple)("N")`

`color(blue)(36)-color(red)(17)=color(purple)(19)"`

The number of neutrons in an atom of `""^36"Cl"` isotope is `19`.

You can write the symbol for the isotope chlorine-36 in nuclear notation (also called isotopic notation) as follows.

`""_17^36"Cl"`

You can subtract the bottom number from the top number to determine the number of neutrons