Question

How many kilograms of water at 15oC can be heated
to 95oC by burning 143 grams of methane, CH4, assuming
that 100% of the heat is used to heat the water.
The heat of combustion of methane is 891 kJ per mole
of methane. (The specific heat of water is 4.184 J/goC.)


I am not sure what to do

Answer 1

Heat obtained from CH4 = 891 kJ x 143/16 = ? kJ.
?kJ = mass H2O x specific heat H2O x (Tfinal-Tinitial)
Solve for mass H2O and convert to kg.

Answer 2

molar mass is 16 for CH4
and answer is 23.8 kg