Chapter 5 - Thermochemistry - Exercises: 5.53b

Increasing the temperature of 1 mol of octane requires more energy.

Work Step by Step

Octane is 2.22 J/g*K. First we need to convert it to the molar heat capacity so we need to find the molar mass. Octane is C8H18. C is 12g/mol and H is 18g/mol so we have: 12*8 = 96 18*1 = 18 Molar mass of C8H18 = 114 g/mol Then we convert the heat capacity as follows: 2.22 J/g*K * 114g/mol = 253.08 J/mol*K For water, the specific heat is 4.18 J/g*K Water is H2O so we find the molar mass. H is 1 g/mol and O is 16g/mol so H2O is 18 g/mol. The molar heat capaity is then: 4.18 J/g*K * 18g/mol = 75.24 J/mol * K Since the molar heat capacity of octane is higher, it requires more energy to raise 1 mole by 1K

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.