Calculate the relative abundance of the europium isotopes??

Question

The element exists in nature as 2 isotopes.
^151Eu has a mass of 152.9209amu.
^153 Eu has a mass of 152.9209 amu.

The average atomic mass of europium is 151.96 amu.

Calculate the relative abundance of the europium isotopes.
pleaseee

give me the equation so i could understand

^153Eu the mass is 152.9209
^151Eu the mass is 150.9196

sryyy thanks

Answer 1

Are you sure those isotope masses are written correctly? They are both the same.

Answer 2

Sorry, but your problem doesn't make sense. How can the two isotopes have exactly the same mass? Isotopes must have different masses because of the difference in their numbers of neutrons. And aren't mass numbers of isotopes always whole numbers, which are the sum of the atom's protons and neutrons? The atomic mass is a decimal since it is an average of the masses of the naturally occurring isotopes.

I will work this problem based on the information on Europium found in the URL below.

Naturally occurring europium is composed of 2 stable isotopes, 151Eu and 153Eu, with 153Eu being the most abundant (52.2% natural abundance). So, 151Eu is second (being 47.8% in abundance).

Atomic Mass = 0.522(153 amu) + 0.478(151 amu)

Atomic mass = 79.866 + 72.178 = 152.044

Answer 3

Europium 151

Answer 4

Well, I think you wrote them incorrectly, but here's what you'd do:

x= abundance of Eu-151 (percentage)
(mass of Eu-151) ( x ) + (mass of Eu-153) ( 1- x ) = 151.96

Solve for x, which will be your abundance for Eu-151. Then solve for the mass Eu-153 by doing (1-x).