Three isotopes of Argon occur naturally:
36Ar (mass = 35.9675 amu)
38Ar (mass = 37.9627 amu)
40Ar (mass = 39.9624 amu)
If the percent abundance of 36Ar is 0.3400, what is the percent abundance of 40Ar?
look up the atomic mass of Ar.
atomicmassAr=.34*35.9675+x*39.9624+(1-x-.34)35.9675) solve for x, you know the avg atomic mass of Ar, from the periodic table.
To find the percent abundance of 40Ar, we need to subtract the percent abundance of 36Ar from 100%.
Percent abundance of 36Ar = 0.3400
Percent abundance of 40Ar = 100% - Percent abundance of 36Ar
= 100% - 0.3400
= 99.6600%
Therefore, the percent abundance of 40Ar is 99.6600%.
To calculate the percent abundance of 40Ar, we can first find the percent abundance of 38Ar and then subtract it from the total abundance.
Let's assume the percent abundance of 38Ar is x.
Since the percent abundance of 36Ar is given as 0.3400 (which can be written as 34.00%), we know that the combined percent abundance of 36Ar and 38Ar is (100 - 34.00)% = 66.00%.
Therefore, the percent abundance of 38Ar is x% and the percent abundance of 36Ar is 34.00%.
The total percent abundance of 36Ar and 38Ar is given by:
Percent abundance of 36Ar + Percent abundance of 38Ar = 66.00%
34.00% + x% = 66.00%
To find the value of x, we can subtract 34.00% from 66.00%
x% = 66.00% - 34.00%
x% = 32.00%
So, the percent abundance of 38Ar is 32.00%.
Now, to find the percent abundance of 40Ar, we can subtract the combined percent abundance of 36Ar and 38Ar from 100%.
Percent abundance of 40Ar = 100% – (Percent abundance of 36Ar + Percent abundance of 38Ar)
Percent abundance of 40Ar = 100% – (34.00% + 32.00%)
Percent abundance of 40Ar = 100% – 66.00%
Percent abundance of 40Ar = 34.00%
Therefore, the percent abundance of 40Ar is 34.00%.