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1. The problem statement, all variables and given/known data

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!

2. Relevant equations

SH of water 4.184kj/g oC

q= specific heat* mass * change in temp

3. The attempt at a solution

Change in temp is 41.6 oC change in H rxn for propane combustion = -2042.804 kj

tried coverting the kg into grams and the 50 gal into grams and plugged in the info for heat lost by tank = heat gained by water (sh*mass*change in t) =-(sh*mass*change in t). I don't know what to use anymore and how to put the problem together because I keep getting ridiculous answers.

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# Homework Help: Thermochemistry please help

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