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Boron has two istopes B^(10) & B^(11) wh...

Boron has two istopes `B^(10)` & `B^(11)` whose relative abundances are `20%` & `80%` respectively avg.atomic weight of Boron is?

A

10

B

11

C

10.5

D

10.8

Text Solution

Verified by Experts

The correct Answer is:
D
Average relative at Wr. A.W. `=(20 xx 10 +80 xx 11)/(100)`
`=(200 +880)/(100) =(1080)/(100) = 10.8g`
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