Let x = abundance of 35 and 1-x = abundance of 37.
Then 35x + 37(1-x) = 35.55
Solve for x and 1-x. and they will be a decimal. Multiply by 100 to convert to percent abundance. Post your work if you get stuck..
Then 35x + 37(1-x) = 35.55
Solve for x and 1-x. and they will be a decimal. Multiply by 100 to convert to percent abundance. Post your work if you get stuck..
Let's assume that the percent abundance of the 35 amu isotope is x% (out of 100%). Since there are only two isotopes, the percent abundance of the 37 amu isotope would be (100% - x%).
The atomic weight is the weighted average of the isotopes, taking into account their masses and abundances. Therefore, we can set up the equation as follows:
(35 amu * x%) + (37 amu * (100% - x%)) = 35.55 amu
Now let's solve for x% to find the percent abundance of the 37 amu isotope.
35x + 37(100 - x) = 3555
35x + 3700 - 37x = 3555
-2x = -145
x = 72.5
The percent abundance of the 37 amu isotope is (100% - x%) = (100% - 72.5%) = 27.5%.