How many grams of nitrogen present in a sample of caffeine

Question

Problem

A. Acetaminophen, the pain-killing ingredient in Tylenol formulations, has the formula C₈H₉O₂ Calculate the mass, in grams, of a 0.30 mole sample of this pain reliever.

B. Carbon monoxide (CO) is an air pollutant that enters the atmosphere primarily in automobile exhaust. Calculate the mass in grams of a 2.61 mole sample of this air pollutant.

C. How many grams of nitrogen are present in a 0.10- g sample of caffeine, the stimulant of coffee and tea? The formula of caffeine is C₈H₁₀N₄O₂.