Some health researchers are investigating the physiological effects of theobromine, C7H8N4O2\text{C}_7\text{H}_8\text{N}_4\text{O}_2C7H8N4O2, a compound naturally found in dark chocolate. Studies suggest that the safe maximum daily intake of theobromine is 2.5×10−4 mol kg−12.5 \times 10^{-4}\text{ mol kg}^{-1}2.5×10−4 mol kg−1. A typical teenager has a mass of 60 kg60\text{ kg}60 kg. A single bar of artisanal dark chocolate contains 540 mg540\text{ mg}540 mg of theobromine.
How many bars of this dark chocolate is it safe for a typical teenager to consume in one day?
(Use the following relative atomic masses: H=1.0\text{H} = 1.0H=1.0, C=12.0\text{C} = 12.0C=12.0, N=14.0\text{N} = 14.0N=14.0, O=16.0\text{O} = 16.0O=16.0)
199 exam-style questions on OCR A A Level Chemistry Atoms and reactions, covering Atomic structure and isotopes, Compounds, formulae and equations, Amount of substance, Acids, and Redox. Each one has a worked solution and a mark scheme showing where the marks go.