# Question #2eec6

##### 1 Answer

Oct 19, 2017

#### Answer:

#### Explanation:

For starters, you already know that **mole** of rubidium has a mass of **molar mass** of

So if you know the mass of *conversion factor* to figure out the number of moles needed to have

#31.018 color(red)(cancel(color(black)("g"))) * "1 mole Rb"/(85.4678color(red)(cancel(color(black)("g")))) = color(darkgreen)(ul(color(black)("0.36292 moles Rb")))#

The answer must be rounded to five **sig figs**, the number of sig figs you have for the mass of rubidium.