A student is asked to determine what mass of butane, C4H10(g), needs to burn in order to raise the temperature of a 1650 g beaker of sand by 180.°C. The student is provided with the equipment shown below. The figure presents a butane burner heating up a beaker of sand. The beaker of sand has a thermometer in it.

a. Calculate the amount of heat energy needed to raise the temperature of the beaker of sand by 180.°C. Assume that all the heat energy from the burner is transferred to the beaker of sand and that the specific heat capacity of the beaker and sand together is 0.810 J/(g×°C).

The student runs the experiment and collects the data shown in the table below.
Mass of beaker and sand: 1650g
Mass of butane burner before combustion: 225.26g
Mass of butane burner after combustion: 218.20g
Initial temperature of the beaker of sand: 20. C
Final temperature of the beaker of sand: 200. C

The figure shows a table with two columns and five rows of data. The first row is titled 'Mass of the beaker and sand’ and lists 1650 grams. The second row is titled 'Mass of butane burner before combustion' and lists 225.26 grams. The third row is titled 'Mass of butane burner after combustion’ and lists 218.20 grams. The forth row is titled 'Initial temperature of the beaker of sand’ and lists 20. degree Celsius. The final row is titled 'Final temperature of the beaker of sand’ and lists 200. degree Celsius.

b. Calculate the number of moles of butane that was used in the experiment. Report your answer to the appropriate number of significant figures.

The combustion of butane is represented by the equation below.
C4H10(g)+132O2(g)→5H2O(g)+4CO2(g) ΔH∘rm=−2659kJ/molrxn

c. Using the balanced equation for the combustion of butane and ΔHrxn°, determine the amount of heat energy produced by the combustion of butane in the experiment.

d. The student claims that some of the heat energy produced by the combustion of butane was lost to the air surrounding the system. Do your answers to parts (a) and (c) support the student’s claim? Explain.