1. (a) A 300.0 g copper kettle contains 1.000 kg of water at 20.0 °C. How much energy must you supply to heat the kettle + water to 98.6 °C? (b) How much propane must you burn to provide this energy, if the transfer of the heat of combustion is 35 %?
#C_text(Cu) = "0.385 J·°C"^"-1"·"g"^"-1"#
#Δ_text(c)H = "2202.0 kJ·mol"^"-1"#
Warning! Long Answer. Here's the answer to Question 1.
a) Energy required
The heat energy
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You have two objects to be heated: the copper kettle and the water.
In this problem,
The energy required is 338 kJ.
b) Mass of propane required
#color(blue)(bar(ul(|color(white)(a/a)q = nΔ_text(c)Hcolor(white)(a/a)|)))" "#
You need to supply 338 kJ of energy to the kettle, but only 35 % of the enthalpy of combustion is actually transferred.
The enthalpy of combustion of propane is -2202.0 kJ/mol.