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Caffeine has a molecular mass of 194. If...

Caffeine has a molecular mass of `194`. If it contains `28.9%` by mass of nitrogen, number of atoms of nitrogen in one molecule of caffeine is :

A

`3`

B

`4`

C

`5`

D

`6`

Text Solution

Verified by Experts

The correct Answer is:
B
Mass of 2 molecular of caffine = 194 amu
N present in one molecule `= (28.9xx194)/(100)`
= 56 amu
56 amu pertains to 4 nitrogen (N) atoms
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