A 1.0 oz piece of chocolate contains 15mg of caffeine, and a 6.0 oz cup of regular coffee contains 105mg of caffeine. How much chocolate in g, Ib, amu, and metric ton would you have to consume to get as much caffeine as you would from 2.0 cups of coffee?

1 Answer
Oct 30, 2015

Here's what I got.

Explanation:

I'll build upon what was already answered here:

http://socratic.org/questions/a-1-0-ounce-piece-of-chocolate-contains-15-mg-of-caffeine-and-a-6-0-ounce-cup-of

So, you know that you must consume #"14 oz"# of chocolate to get as much caffeine as you would from #"2.0"# cups of coffee.

To get this value to grams, pounds, unified atomic mass units, and metric tons you need to use the following conversion factors

#"1 oz " = " 28.3495231 g"#

#"1 lb " = " 453.59237 g"#

#"1 u " = 1.66 * 10^(-24)"g"#

#"1 g " = 10^(-6)"t"#

So, let's start converting

#14color(red)(cancel(color(black)("oz"))) * "28.3495231 g"/(1color(red)(cancel(color(black)("oz")))) = 4.0 * 10^2"g"#

#4.0 * 10^2color(red)(cancel(color(black)("g"))) * "1 lb"/(453.59237color(red)(cancel(color(black)("g")))) = "0.88 lb"#

#4.0 * 10^2color(red)(cancel(color(black)("g"))) * "1 u"/(1.66 * 10^(0-24)color(red)(cancel(color(black)("g")))) = 2.4 * 10^(26)"u"#

#4.0 * 10^2color(red)(cancel(color(black)("g"))) * (10^(-6)"t")/(1color(red)(cancel(color(black)("g")))) = 4.0 * 10^(-4)"t"#