Question
PRE-LABORATORY STOVE TOP THERM6CHEMISTRI calculate the amount heat (a) produced by the co of 4.05 gCH (AH sooA kly. of Consider that the 4.05 g methane is burned and all of the heat from this combustion is absorbed by 1.0 kg of 20. "C water the pot holding the water, and use 4.18 J gi for the specific heat of the water). What would be the final temperature of the water? First, rearrange equation to solve for AT. Show your rearrangement of equation 3 below. Now, plug into your equation the values for q, m, and c to find 4T (be mindful of your kl and J units). Finally, knowing 4Tand the initial temperature, Th find the final temperature,TF of the water.
Explanation / Answer
moles of methane = 4.05 g/16 g/mol = 0.253 mol
Heat evolved by combustion of methane = 0.253 x -890.4 = -225.38 kJ
Heat absorbed by water = 225.38 kJ
So,
dT = heat/mCp
= 225380/1000 g x 4.18
= 53.92 oC
final temperature of water = 53.92 - 20 = 33.92 oC