# What species is represented by the following information? p^+ = 14, n^o = 12, e^(-) = 10

Aug 31, 2016

${\text{_14^26"Si}}^{4 +}$

#### Explanation:

Right from the start, you should know that the number of protons gives you the identity of the element.

Each element listed in the Periodic Table has a unique atomic number, i.e. each element has a unique number of protons located inside its nucleus.

So, your atom contains $14$ protons inside its nucleus. Grab a periodic table and look for the element that has an atomic number equal to $14$.

You can thus say that you're dealing with silicon, $\text{Si}$.

Now, a neutral atom of silicon will have $14$ protons inside its nucleus and $14$ electrons surrounding its nucleus. In your case, the atom has $10$ electrons surrounding the nucleus, which means that you're dealing with an ion.

More specifically, you're dealing with a positively charged ion, i.e. a cation. The charge of the cation is given by the difference between the number of protons and the number of electrons

${\text{charge" = "14 p"^(+) - "10 e}}^{-} = 4 +$

Therefore, you can say that you're dealing with a ${\text{Si}}^{4 +}$ cation.

Finally, you can use the number of neutrons to find the mass number, $A$, of the cation. As you know, the mass nubmer is equal to

$A = Z + {n}^{0}$

$A = {\text{14 p"^(+) + "12 n}}^{0} = 26$
The tells you that you're dealing with the $4 +$ cation of a neutral silicon-26 atom. In isotope notation, this is written as
${\text{_14^26"Si}}^{4 +}$