A substance has an empirical formula of #CH_2# and a molar mass of 56 grams per mole. What is the molecular formula for this compound?

1 Answer
Jan 3, 2017

The molecular formula is always a whole number multiple of the empirical formula, so.........

Explanation:

#("empirical formula")xxn="Molecular formula"#,

i.e. #(12.01+2xx1.00794)*g*mol^-1xxn=56*g*mol^-1#

#n=(56*g*mol^-1)/((12.01+2xx1.00794)*g*mol^-1)#

And clearly, #n=4#.

So #"molecular formula"# #=# #(CH_2)_4#

#=C_4H_8#

The stuff is a butylene OR a three-membered or four-membered ring.