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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%` Its average atomic mass is

A

199amu

B

200amu

C

201 amu

D

202amu

Text Solution

Verified by Experts

The correct Answer is:
B
Average atomic mass of X
`=0.9xx200+0.08xx199+0.02xx202`
`=180+15.92+404=199.96`
`=200` amu
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