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A. How many cups of coffee would be too much and at the dangerous level (of
3.00 g)? You know that coffee contains 21.5 mg caffeine per ounce and cola
contains 4.20 mg per ounce and a cup is 8 oz. and a can is 12.0 oz.

Respuesta :

Given :

Mass of caffeine at dangerous level , m = 3 g .

Coffee contains , 21.5 mg/oz OF caffeine .

Mass of cup , 8 oz/cup .

To Find :

Number of cups till dangerous level .

Solution :

Caffeine in a cup of coffee is given by :

[tex]C=(21.5\ mg/oz)\times (8\ oz/cup)\\\\C=172\ mg/cup\\\\C=0.172\ g/cup[/tex]

Now , number of cups at the dangerous level is given by :

[tex]n=\dfrac{3\ g}{0.172\ g/cup}\\\\n=17.44\ cups[/tex]

Now , number of cups should be integer .

Therefore , 18 cups of coffee per day is dangerous .

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