Question #b4ab9

1 Answer
Oct 23, 2017

Here's what I got.

Explanation:

For starters, calculate the charge of the ion by using the equation

color(blue)(ul(color(black)("net charge" = "no. of protons " - " no. of electrons"

In your case, you have

"net charge" = 52 - 54 = -2

This tells you that the ion carries a 2- charge, which implies that you are dealing with a negatively charged ion, or anion.

Now, the isotope notation of this ion requires

  • the atomic number of the element, Z
  • the mass number of the isotope, A

http://chemkjj.blogspot.ro/2015/06/c1-12-proton-number-mass-number-ions.html

In your case, you know that the element has 52 protons, which means that

Z = 52

In order to find the mass number of the isotope, simply add the number of protons and the number of neutrons present in the nucleus.

A = "52 protons + 76 neutrons"

A = "128 nucleuons"

This means that the symbol of the neutral isotope will look like this

""_(color(white)(1)52)^128"X"

A quick look in the Periodic Table will reveal that you're dealing with tellurium-128, an isotope of tellurium, "Te".

""_(color(white)(1)52)^128"Te"

Finally, to show that this is an anion and not a neutral atom, add the net charge.

""_(color(white)(1)52)^128"Te"^(2-)