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Ali73
Oct 24, 2011, 07:40 PM
1.)
inital temp. is 21 C
finial temp. is 30.3 C
change in temperature is __________________?
initial weight of candle = 13.113 g
final weight of candle = 12.945 g
Amount of candle burned = _________?

heat absorbed by water (q)=s*m*delta T (assume volume of water equals to mass of water, since density = 1.00 g/mL). s (specific heat of water = 4.184 J/g C).

a.) calculate the amount of heat absorbed by the water in the experiment?

b.) how many heat did candle burned in the experiment?

c.) calculate the heat released per gram of candle burned?


2.) what are the chemical equations that are useful for determining the heat of solution, the heat of reaction, the heat of combustion.

Unknown008
Oct 25, 2011, 02:22 AM
1. Find the difference in temperature.
Find the difference in candle.

a. Use the given formula. What do you come up with?
b. This is the same amount as you got in a.
c. This is the heat released by the candle for the difference in mass of the candle. Can you find the heat per gram, using proportions?

2. Well, I don't think the question is well being asked here... there are different chemical equations for different reactions, but for the case of candle, it would be the combustion/reaction of the fat in the candle.

As for the heat of solution, it depends on the reagents.