What does the 80 stand for in Bromine-80?

Answer 1

This is the mass number of the specific isotope. Since the atomic number of bromine is 35, bromine-80 has 35 protons and 45 neutrons.

Bromine-80 can also be written in formulas as 80Br.

Answer 2

Usually, a number stated with an element is used to identify the different isotopes of that element. (Isotopes are different atoms of the same element that have different atomic masses--that is, the number of neutrons in the nucleus is different.) The "80" refers to the number of nucleons--protons and neutrons--in the nucleus. (As electrons have such low mass and are not part of the nucleus, they are ignored when calculating Atomic Mass.) Since bromine has an atomic number of 35, there are 35 protons in the nucleus; the difference between 80 and 35 tell us the number of neutrons. So an atom of bromine-80 contains 35 protons, 35 electrons, and 45 neutrons.

Answer 3

Usually, when there is a number following an element, it tells you which isotope it is. Each element has a specific amount of Protons and Electrons, but the Neutrons in an element will vary; this determines its isotope. In this example, Bromine8 is just bromine with 8 neutrons.

Answer 4

The number 80 in Bromine-80 represents the mass number (protons + neutrons) of the isotope bromine-80. It is used to distinguish this particular isotope from other isotopes of bromine with different mass numbers.