Entropy: Understanding the Concepts and Comparisons
Which system has greater entropy between 1 mol of H2(g) at STP and 1 mol of SO2(g) at STP?
a) 1 mol of H2(g) at STP or 1 mol of SO2(g) at STP
b) 1 mol of N2O4(g) at STP or 2 mol of NO2(g) at STP
Answer:
a) 1 mol of SO2(g) at STP has greater entropy than 1 mol of H2(g) at STP.
b) 1 mol of N2O4(g) at STP has greater entropy than 2 mol of NO2(g) at STP.
Entropy is a crucial concept in thermodynamics that measures the disorder or randomness of a system. It helps us understand the behavior of molecules and predict their direction of change in a given system.
Entropy of 1 mol of H2(g) and 1 mol of SO2(g) at STP
The system with greater entropy between 1 mol of H2(g) and 1 mol of SO2(g) at STP can be determined by considering their molecular masses and the number of moles. At STP, 1 mol of H2(g) occupies a volume of 22.4 L and has a molecular mass of 2 g/mol. Similarly, 1 mol of SO2(g) occupies a volume of 22.4 L and has a molecular mass of 64 g/mol.
The entropy of a system is directly proportional to the number of particles present in it, so the system with greater entropy will have more particles. As 1 mole of SO2(g) has more particles than 1 mole of H2(g), it will have a greater entropy. Therefore, the system with greater entropy between 1 mol of H2(g) and 1 mol of SO2(g) at STP is 1 mol of SO2(g).
Entropy of 1 mol of N2O4(g) and 2 mol of NO2(g) at STP
The system with greater entropy between 1 mol of N2O4(g) and 2 mol of NO2(g) at STP can be determined by considering the degree of molecular complexity. At STP, 1 mol of N2O4(g) occupies a volume of 22.4 L and has a molecular mass of 92 g/mol. On the other hand, 2 mol of NO2(g) occupy a volume of 44.8 L and have a molecular mass of 46 g/mol.
The entropy of a system is directly proportional to the degree of molecular complexity. As N2O4(g) is a larger and more complex molecule than NO2(g), it will have more entropy. Therefore, the system with greater entropy between 1 mol of N2O4(g) and 2 mol of NO2(g) at STP is 1 mol of N2O4(g).
Understanding these comparisons can help us comprehend the factors affecting the entropy of a system and make informed decisions in thermodynamic processes.