What does #"X"# represent in the following symbol: #""_35^80"X"# ?

2 Answers
Aug 27, 2016

Answer:

Do you mean #35/80X#? That should be Bromine

Explanation:

X shows the name of the element in the periodic table

Sep 4, 2016

For #""_(35)^(80) X#, recall that the isotope notation uses the following symbols:

#bb(""_(Z)^(A) X^(pmn))#

  • #Z# is the atomic number, which tells you the number of protons in the element and also its identity.
  • #A# is the mass number, which tells you the number of protons plus the number of neutrons.
  • #X# is the chemical symbol of the element, and it must correspond to the atomic number.
  • #pmn# is the signed charge.

So, with an atomic number of #35#, we look at the fourth period and seventh group/column to get #"Br"#, or bromine. With a mass number of #80#, we have the #"Br"-80# isotope.