1. Burning butane (C4H10) produces gaseous carbon dioxide and water.

AI Thread Summary
Burning butane (C4H10) produces carbon dioxide and water, with an enthalpy of combustion of -2650 kJ/mol. Calculating from 1 kg of butane yields approximately 17.20 moles, which can produce about 1.549 kg of water. The discussion emphasizes using the enthalpy of combustion to determine the energy available for heating water from room temperature (22°C) to boiling. Participants suggest applying the equation q = mc(delta)T to find the temperature change and the amount of water that can be heated. The focus remains on understanding the energy conversion and the relationship between butane combustion and water heating.
recoil33
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1. Burning butane (C4H10) produces gaseous carbon dioxide and water. The enthalpy of combustion of butane is -2650 kJ/mole. Determine how much water you can heat from room temperature (22 Degrees) to boiling with 1 kg of butane.

Therefore:

13O2 + 2C4H10 ---Heat---> 8Co2 (g) + 10H2O(l)

n(H2o) = 10 n(c4h10)

Enthalpy (c4h10) = -2650 kJ/mol
Temp (initial) = 22.0 degrees celcius
Mass (c4h10) = 1kg.
-------------------------------------------------------

n(c4h10) = 1000/58.12
= 17.20mol

(Although C4H10 would be a liquid therefore n = cV, wheres i do not know the concentration).

n(h20) = 5n(c4h6)
n(h20) = (17.20*5) * (18.016) =
= 1549g

m(h20) = 1.549kg

Now, to figure out how much the change in temperature will be. I assume use the equation q = mc(delta)T.


[Any advice please, don't reallly know where to start.
I should be able to figure this out, once i know where from.
]
Thanks, recoil33
 
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I'm not following some of your notation, but here is what I would do-

Find out how many moles of Butane you have, which I think you did.

Next, use the enthalpy of combustion to find out the total amount of energy you can get from 1 Kg of butane. Next, use that value as your 'q' in your mc(delta)t equation and solve for m.

If your final answer needs to be a volume, use the density of water to convert.

I don't think this problem has anything to do with the water created by the combustion of Butane.
 


Sorry, I didn't even read the question right -.-'

It's really simple, thanks anyways.

(I didn't realize that they said given 22-100 degrees, whereas i thought the change in temperature was unknown, as well as the mass.)
 
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