A 3.000 gram sample of an unknown compound containing the elements carbon, hydrogen, and nitrogen is analyzed by combustion. The combustion releases 4.714 grams of carbon dioxide and 1.500 grams of nitrogen. If 25 molecules have a combined mass of 4.65 x 10⁻²¹ grams, what is the compound's molecular formula?
Chemistry - DrBob222, Tuesday, October 18, 2011 at 9:19pm
Convert 4.714g CO2 to g C.
Convert 1.500g N2 to g N.
g H = 3.00-gC-gN
moles C = ?
moles H = ?
moles N = ?
Find the empirical formula.
The molar mass will be
4.65E-21 x (6.022E23/25) = ?
Then (molar mass/empirical mass) = n which you round to a whole number, then
molecular formula = (empirical formula)n
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