Question

The Mayo Clinic website has the following statement: “Up to 400 milligrams (mg) of caffeine a day appears to be safe for most healthy adults.” It is possible to “overdose” on caffeine! According to the Starbucks™ website a Venti (20 oz) Blonde Roast coffee contains 475 mg of caffeine. The recommended use guidelines for “5-Hour Energy® shots” clearly states that you should not take consume more than 2 bottles daily.

(a) How many ounces of Blonde roast coffee (rounded to one decimal place) will contain 400 mg of caffeine? (

b) How many ounces of caffeine do you think each 5-Hour Energy® shot should contain? Give a reason for your answer.

(c) How many ounces of caffeine does each 5-Hour Energy® shot should contain? Give a source for your answer.

Answer 1

a)

20 oz of Blonde Roast coffee contains 475 mg of caffeine

Then 1 mg of caffine is contained in

= 20 / 475

= 0.042 oz.

400 mg of caffine is contained in 400 x 0.042 = 16.8 oz of Blonde Roast coffee.

b)

Since Mayo Clinic website states that “Up to 400 milligrams (mg) of caffeine a day appears to be safe for most healthy adults.” and the recommended use guidelines for “5-Hour Energy® shots” states that we should not take consume more than 2 bottles daily it implies that 2 bottles of “5-Hour Energy® shots” contains 400 mg of caffine.

So each “5-Hour Energy® shots” should contains 200 mg of caffine

1 mg = 3.5274e-5 oz

200 mg = 0.00705479 oz

So we think each “5-Hour Energy® shots” contain 0.007055 oz of caffine.

c)

According to Consumer Reports Website. https://www.consumerreports.org/cro/magazine/2012/12/the-buzz-on-energy-drink-caffeine/index.htm

5-Hour Energy® shots contains 215 mg of caffine.

So 5-Hour Energy® shots actually contains 0.007584 oz of caffine