HELP! Moles[Chemistry]?

So I started in a new school and I'm totally behind because they started a month earlier. Please help me!


okay, the question asks how many moles is each of the following:





a.)1.50 x 10E23 molecules NH3


I got 2.491 x 10E45 moles of NH3





b.)1 billion( 1 x 10E9) molecules 02


I got 1.661 x 10E31 moles of 02





c.)6.02 x 10E22 molecules Br2


I got 1 x 10E45 moles of Br2





d.)4.81 x 10E24 atoms Li


I got 7.990 x 10E46 moles of Li





I'm pretty sure I got most of them wrong, I'm confused on how you do it and how you round it up to its significant number.


please help!





thank you in advance!

HELP! Moles[Chemistry]?
click on the link below, it will help you.


http://antoine.frostburg.edu/chem/senese...


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however i solved the 1st one fore you


1.50 x 10E23 molecules NH3 * (1 mole NH3/6.02×10E23molecules NH3) = 0.2491 mole NH3


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Reply:hahaha I done this in chemistry too





did your teacher taught you the mole hill trick?


sorry man is winter break and I forgot everything.
Reply:In each of these you have to divide the given no. by 6.022 x 10^23.





Hope this helps.





your_guide123@yahoo.com

camellia