Caffeine (molecular weight = 194) contains 28.9% nitrogen. The number of nitrogen atoms in caffeine molecule is:
Correct answer: B. 4
- A. 2
- B. 4
- C. 7
- D. 8
Explanation
Mass of nitrogen in 194 amu caffeine N= 28.9gN= 28.9 /100N= 28.9/100 x194 ∴ One molecule of caffeine will contain =56 /14 which is equal to 4 nitrogen atoms
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