Caffeine, a natural stimulant commonly found in tea and coffee, reacts with water accordingtothe following equation: \mathrm{C}_{8} \mathrm{H}_{10} \mathrm{~N}_{4} \mathrm{O}_{2}(a q)+\mathrm{H}_{2} \mathrm{O}(I) \rightleftharpoons \mathrm{HC}_{8} \mathrm{H}_{10} \mathrm{~N}_{4} \mathrm{O}_{2}^{+}(a q)+\mathrm{OH}^{-}(a q) a) What is the molar mass and percent composition of caffeine? b) Using the determined percent composition of caffeine, what is the empirical formula of caffeine (show your derivation for full marks)? c) A 250 ml can of Red Bull contains 77.4 mg of caffeine. How many moles and molecules of caffeine are in three cans of Red Bull? d) There is 94.8 mg of caffeine in a standard cup of coffee (200 mL). What is the molar concentration of caffeine in 150 mL of coffee?

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