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Help please!!!! Enthalpy ... and more!

Submitted by AshleeH on Thu, 07/01/2010 - 01:37

Consider the following thermochemical equation for the combustion of acetone (C3H6O), the main ingredient in nail polish remover.

C3H6O (l) + 4 O2 (g) ---> 3 CO2 (g) + 3 H2O (g)
Change H degrees rxn = -1790 kJ

If a bottle of nail polish remover contains 177ml of acetone, how much heat would be released by its complete combustion? The density of acetone is 0.788 g/mL.

If you could show what formula you used and what part density plays also. I just can't figure out how they got to the answer: -4.30 x 10^3 kJ

Use density to find the mass of 177ml of acetone as each mL has a mass of 0.788g.
(mass = density x volume)

Then find the molar mass of acetone.

eg if C3H6O has a molar mass of 58g (using simple atomic masses), then 58g releases 1790kJ.
Then find the amount of heat released by (177 x 0.788)g of acetone