how do I set this up?
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Answer: -
280mg
Explanation: -
The chemical formula is C14H18N2O5
Molar mass of the compound = 12 x 14 + 1 x 18 + 14 x 2 + 16 x 5 = 294 gram
Number of nitrogen atoms present in the formula = 2
Mass of nitrogen present= 14 x 2 = 28 gram
Thus 294 gram of the compound has 28 gram.
Hence 2.95grams of the compound has (28 gram x 2.95 gram / 294 gram)
= 0.28 gram
= 280 mg
Thus 280 mg of nitrogen is present in 2.95 grams of C14H18N2O5