A research article indicates that researchers have used an isotope #"^3H# ti trace a certain metabolic process. From the symbol that is given, how many proton, neutrons, and electrons does this hydrogen isotope have?

1 Answer
Oct 2, 2016


A neutral, isolated tritium atom, #""^3H#, has 1 nuclear proton, 2 neutrons, and the 1 electron.


Protons are massive, positively charged nuclear particles; neutrons are massive, neutrally charged nuclear particles. When we write #""^3H# we immediately specify that the number of nuclear protons is #1#, because that is how the element hydrogen is described, and that there are 2 neutrons in addition.

In this hydrogen nucleus, 2 neutrons are thus present, because the number of massive #"nucular"# particles give the superscript on the atomic symbol, the isotopic mass number. Finally, because the overall charge on the atom is zero, there must be 1 electron, 1 fundamental negative charge, whizzing about the nucleus. Capisce?

It you have any queries, come back with them, because it is very worth while getting the basics of atomic structure right the first time.

Can you give the same treatment for the #"deuterium isotope"#, #""^2H#? Deuterium labels are very commonly used in chemistry laboratories.