Thread: Moles(unit)

how many grams of water in 5 moles of water?


how many moles of CO2 would be needed to have a mass of 100 grams?

Originally Posted by MoltenWhale

how many grams of water in 5 moles of water?

The molecular weight of water is 2*1+16=18, so one mole of water is 18 grams. 5 moles are 5*18=90 grams.

Originally Posted by MoltenWhale

how many moles of CO2 would be needed to have a mass of 100 grams?

A mole of is 48 grams, so 100 grams is just a little over 2 moles.

HTH,
L.

Originally Posted by Leszek Luchowski

Originally Posted by MoltenWhale

how many moles of CO2 would be needed to have a mass of 100 grams?

A mole of is 48 grams, so 100 grams is just a little over 2 moles.

A mole of carbon dioxide is 44 grams, not 48. And this seems like a homework question, and we shouldn't be doing it for him. The answers should be very easy to obtain with a little research if it's homework for a chemistry class or something...

Originally Posted by Chemboy

A mole of carbon dioxide is 44 grams, not 48.

You're right, my mistake.

Originally Posted by Chemboy

And this seems like a homework question, and we shouldn't be doing it for him. The answers should be very easy to obtain with a little research if it's homework for a chemistry class or something...

Right again. I thought I was answering to an inquisitive mind who wanted the principle illustrated by example (can be easier than an abstract definition), and I still have some hope this is the case - but a lot of kids I know would just copy the answer into their book and never try to understand it. Which of course is counterproductive.

Thanks for your comment. Next time I'll try to help in a wiser way.

Cheers, L.