# What element can be represented by 45 n^o, 34 p^+, 34 e^.?

Sep 2, 2016

If there are $34$ $\text{protons}$, the element is unquestionably $\text{selenium}$.

#### Explanation:

The number of protons, the number of massive, positively charged nuclear particles, is $Z , \text{the atomic number}$. $Z$ unequivocally defines the identity of the element. For $Z = 34$ we have selenium.

We can be even more specific than this, because the question reported the number of neutrons, the number of neutrally charged, nuclear particles, i.e., the ""^79Se isotope, where the $79$ superscript is the isotopic mass: $\text{neutrons + protons}$. And thus this isotope possesses $79 - 34 = 45 \text{ neutrons}$

The problem specified $\text{34 electrons}$, so we know that this is a neutral element. Why?

I haven't looked this up yet, but I think that this is a fission product, i.e. an unusual selenium isotope.