Percent Abundace Calc Error

  • Thread starter BrianC
  • Start date
  • #1
BrianC
3
0
% Abundace Calc Error

here's the prob and my work can anyone help me figure out where i'm going wrong? thanks

The element silver has two naturally occurring isotopes with masses of 106.91 amu and 108.90 amu. What would be the percent abundance of the first isotope, if the atomic weight were 108.0429 amu?

108.0429 = 106.91*X + 108.90*Y (and since Y=1-X)
108.0429 = 106.91*X + 108.90 - 108.90*X
108.0429 - 108.90 = 106.91*X + 108.90*X
-(-1.99 = -0.8571*X) = 1.99 = 0.8571*X
X = 0.4307
Y= 0.5693

i did that and the online thing i enter the homework into says it's incorrect :confused:
 

Answers and Replies

  • #2
BrianC
3
0
little typo in there the third line of my work should be
108.0429 - 108.90 = 106.91*X - 108.90*X
 
  • #3
BrianC
3
0
-(-1.99 = -0.8571*X) = 1.99 = 0.8571*X
should be -(-1.99X = -0.8571) = (1.99X = 0.8571)
 
  • #4
Sirus
574
2
Try converting your answers to percentage values instead of decimals.
 

Suggested for: Percent Abundace Calc Error

Replies
7
Views
532
  • Last Post
Replies
1
Views
232
Replies
6
Views
273
Replies
4
Views
149
  • Last Post
Replies
7
Views
331
Replies
4
Views
354
  • Last Post
Replies
3
Views
314
Replies
2
Views
367
Top