What result do you get when you multiply the number of moles of a sample by the following conversion factor? (g of element)#/#(1 element)

1 Answer
Dec 1, 2016

Answer:

I think you mean to multiply the mass of an element by #1/("molar mass of the element")#

Explanation:

And if we do this we get:

#"mass of the element (g)"/("molar mass of the element"(g*mol^-1))#, we get an answer in #"moles"#, because, #g/(g*mol^-1)=cancelg/(cancelg*mol^-1)=1/(1/(mol^-1))=mol# as required.

So if I have #12*g# of carbon, I have a molar quantity of #(12*cancelg)/(12.011*cancelg*mol^-1)~=1*mol#.

The quotient gives an answer in #"moles"# dimensionally.

From where do I get the molar masses? Have I memorized them? Do you have to memorize them for an exam?

Actually, you will memorize the more common molar masses, i.e. those of oxygen, nitrogen, carbon, sodium, iron...........