Question

Which substances in each of the following pairs would have the greater entropy? Explain.

(a) at 75°C and 1 atm: 1 mol H2O(l) or 1 mol H2O(g)

(b) at 5°C and 1 atm: 50.0 g Fe(s) or 0.80 mol Fe(s)

(c) 1 mol Br2(l,1 atm, 8°C) or 1 mol Br2(s, 1 atm, -8°C)

(d) 0.312 mol SO2 (g, 0.110 atm, 32.5°C) or 0.284 mol O2(g, 15.0 atm, 22.3°C)

My answers:

a) 1 mol of H2O(g) would have the higher entropy becasue since both items being compared are at the same temperature and pressure, we can determine which one has the higher entropy by choosing the one which has the state of greater microstates, that is gas between gas and solid states.

b) I'm not sure how to approach this part. If someone could help, it'd be appreciated.

c) 1 mol of Br2(l) at 1 atm and 8°C because at higher temperatures there are greater number of microstates and there are also greater number of microstates in a liquid state than a solid state.

d) not sure. please help!

Answer 1

b) if you convert 50g Fe to mol by divide by the molar mass you get 0.89 which is higher than the second choice
d) the higher temperature is the correct one

answering way too late but it will help for anyone who needs this later on