Answer:
X = 48.014%
Y = 51.986%
Step-by-step explanation:
Given
151 EU has a mass of 150.9196 amu
153 EU has a mass of 152.9209 amu
Calculating the relative abundance of the two EU isotopes.
First condition that must be satisfied is
X + Y = 100%;
X + Y = 1. ----- Equation 1
Second Condition is;
150.9196X + 152.9209Y = 151.96 ------ Equation 2
In Equation 1; make Y the subject of formula.
So, Y = 1 - X.
Substitute (1 - X) for Y in Equation 2
150.9196X + 152.9209(1 - X) = 151.96 ----Open bracket
150.9196X + 152.9209 - 152.9209X = 151.96 ---- Collect Like Terms
150.9196X - 152.9209X = 151.96 - 152.9209
−2.0013X = -0.9609
X = -0.9609/-2.0013
X = 0.480137910358267
X = 48.014% ----- Approximated
Y = 1 - X
Y = 1 - 48.014%
Y = 0.51986
Y = 51.986% ---- Approximated