Question

Question #f6b8c

Answer 1

`4.187 * 10^(25)`

Explanation:

For starters, you know that each molecule of carbon dioxide, `"CO"_2`, contains

• one atom of carbon, `1 xx "C"`
• two atoms of oxygen, `2 xx "O"`

This means that every mole of carbon dioxide will contain `2` moles of oxygen atoms.

You can thus say that your sample will contain

`34.77 color(red)(cancel(color(black)("moles CO"_2))) * "2 moles O"/(1color(red)(cancel(color(black)("mole CO"_2)))) = "69.54 moles O"`

Now, in order to have `1` mole of oxygen atoms, you need to have `6.022 * 10^(23)` atoms of oxygen `->` this is given by Avogadro's constant.

This means that your sample will contain a total of

`69.54 color(red)(cancel(color(black)("moles O"))) * (6.022 * 10^(23)color(white)(.)"atoms O")/(1color(red)(cancel(color(black)("mole O"))))`

`= color(darkgreen)(ul(color(black)(4.187 * 10^(25)color(white)(.)"atoms O")))`

The answer is rounded to four sig figs, the number of sig figs you have for the number of moles of carbon dioxide.