Answer:
given an element U of relative atomic mass 10.8 for example with isotopes U-10 and U-11 we can get their percentages by the following steps.
Step-by-step explanation:
1:let the Percentage of U-10 equal to X% and percentage of U-11equal to Y%.
2:The addition of X% and Y% equal to 100%.
3:X%=100%-Y%
4:X% of U-10 +Y% of U-11=10.8
5: substitute 3 in 4.
6: i.e (100-Y)% of U-10+Y% of U-11=10.8.
7:(100-Y)/100 of 10 +Y/100 of 11=10.8.
8:100-Y/10 +11Y=10.8.
9:(1000-10Y+11Y)/100=10.8.
10:1000+Y=10.8*100
11:1000+Y=1080.
12:Y=1080-1000.
13:Y=80.
14: from 3,X=100%-Y%.
X=100%-80%=20%.
15: Therefore, the percentage of isotopes in the isotopic mixture are 20% U-10 and 80% U-11.