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An element X has the following isotopic ...

An element X has the following isotopic composition :
`.^(200)X:90%," ".^(199)X:8.0%," ".^(202)X:2.0%`
The weighted average atomic mass of the naturally occurring element X is closest to :

A

199 amu

B

200 amu

C

201 amu

D

202 amu

Text Solution

Verified by Experts

The correct Answer is:
B
`bar(A)=Sigmaf_(i)A_(i)f_(i)=" fractional abudance, "A_(i)="atomic masss"`
`=0.90xx200+0.08xx199+0.02xx202`
`=180+15.92+0.04~~200`
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