Question #2eec6

1 Answer
Stefan V.
Oct 19, 2017

"0.36292 moles"

Explanation:

For starters, you already know that 1 mole of rubidium has a mass of "85.4678 g" because rubidium has a molar mass of "85.4678 g mol"^(-1).

So if you know the mass of 1 mole of rubidium, you can use it as a conversion factor to figure out the number of moles needed to have "31.018 g".

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.

Related questions
See all questions in The Mole
Impact of this question
1606 views around the world
You can reuse this answer
Creative Commons License