Question

Question #e4dde

Answer 1

`1.56 xx 10^21` `"atoms Na"`

`= 0.00259` `"mol Na"`

`= 0.0596` `"g Na"`

Explanation:

Your answer is in the question: `1.56 xx 10^21` atoms of `"Na"` is equal to `1.56 xx 10^21` atoms of `"Na"`.

If you would like to find the number of moles present, you can use Avogadro's number to find this:

`1.56 xx 10^21 cancel("atoms Na")((1color(white)(l)"mol Na")/(6.022 xx 10^23cancel("atoms Na")))`
`= color(red)(0.00259` `color(red)("mol Na"`

You can also find the mass of sodium present, using the molar mass of sodium, `22.99"g"/"mol"` (found on a periodic table):

`color(red)(0.00259` `cancel(color(red)("mol Na"))((22.99color(white)(l)"g Na")/(1cancel("mol Na"))) = color(blue)(0.0596` `color(blue)("g Na"`