Assume that 4.08 x 106 kJ are needed to heat a swimming pool. If this energy is derived from the combustion of liquid ethanol (CH3CH2OH) at standard conditions (25 oC and 1 atm) what volume in liters of ethanol must be burned?
The heat of combustion of ethanol is 1366.818 kJ/mol. The density of ethanol is 0.789 g/cm3
Enter a numeric answer only. Do not enter units.
I tried 166465847.8 and 166.4658 but they both came up wrong
2007-01-31 12:22:24 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
4.08 x 10^6 KJ x (1 mole / 1366.818 KJ ) x (46 g / mole ) x (1 cm^3 / .789 g ) x ( 1 liter / 100 cm^3) = 1740 liters.
with 3 sig figs.
2007-01-31 12:43:14 · answer #1 · answered by Dr W 7 · 1⤊ 0⤋
ok, so to get that 4.08 * 10^6 kJ, you would need to burn x moles of ethanol, each releasing 1366.818 kJ of energy. so divide that 4.08 *10^6 by 1366.818 and you'll get the moles you need. once the division is over, you need to burn 2,985 moles of ethanol (which is a hell of a lot!!). so, by using PVnRT, you get the equation (1atm)(V)=(2985 moles)(.0821 atmL/molK)(298 K) and just solve for V.
V=73,030 L give or take a few tenths.
2007-01-31 12:46:05 · answer #2 · answered by The Frontrunner 5 · 0⤊ 1⤋
all of us understand from the formula that there are 9 moles of oxygen atoms to each and each mole of the compound, this means that we in simple terms might desire to paintings out what number moles of the compound are in 21.3g. The atomic weights are: Al - 27 N - 14 O - sixteen this means that the molar weight of the compound is Al + 3N + 9O 27 + 40 two + one hundred forty four 213 g/mol From this we are able to be certain that we 0.a million moles of the compound. considering the fact that all of us understand that there are 9 moles of oxygen atoms in each and each mole of compound then all of us understand that we've 0.9 moles of oxygen atoms. a million mole of oxygen atoms includes 6.022*10^23 atoms then 0.9 moles includes 5.420 * 10^23 oxygen atoms. With the uranium 235 all of us understand that there are 6.022*10^23 uranium atoms in 235g for this reason the mass of one atom is 235 / 6.022*10^23 = 3.902 × 10^-22 g to place it yet differently a million atom of U-235 weighs 390 yoctograms
2016-12-17 06:46:41 · answer #3 · answered by ? 3 · 0⤊ 0⤋