[Charolastra633]

Not sure how to go about this problem.

Calculate the number of grams of propane (C3H8) required to heat all of the water in a 50-gallon hot-water tank from 23.4 degrees C to 65.0 degrees C if the water tank itself has a heat capacity of 23.4J/ degrees C, and it also uses 2.3 kg of copper pipe.

HELP PLEASE!

[enahs]

http://www.chemicalforums.com/index.php?topic=9037.0
Number 4. We want to help, we do not want to do your work for you.

[Charolastra633]

oh i have tried/ I just don't know how to factor in the copper pipe's weight and i tried coversion factors and found the change H rxn to be -2042.804kj but i just don't know how to put it together, I have been trying various ways, trust me.  I don't know if you use something with heat lost by tank = heat gained by water and q=sh * mass * change in temp. for mass we are looking for grams but what do we do with the 50 gallons?

[enahs]

I believe the way you have written it is a little confusing, and maybe you are confusing yourself. The tank is made from the copper pipe, and the tank weights 2.3 kg. It does not mean a tank + another copper pipe, just that the tank weights 2.3 kg.

[Charolastra633]

ahh i am still not getting it. i don't know what strategy to try next.

[Charolastra633]

Please, will you please, tell me if this answer is wrong because i came up with a method with my friend and we are dying to know if we are even close. 710.840g

[Mitch]

http://www.chemicalforums.com/index.php?page=forumrules

[Charolastra633]

i read them, my friend and i spent so much time on this problem and different methods, it would be nice to know that our work paid off or not. I am not just trying to get the answers but I am sick of wasting so much time on one problem.

[Borek]

So please show your work. So far you have repeated several times that you did the question - but we can't tell you what is wrong or OK about it not seeing the method and the math.