Chem 230 Exam 2| 317 Questions| With Complete Solutions

What is the third law of thermodynamics? correct answer: The entropy of a perfect crystal is zero. What is the second law of thermodynamics? correct answer: As a whole, the universe always tends towards increasing entropy. What is the relationship between number of microstates and entropy? correct answer: More microstates = higher entropy What is the relationship between temperature and entropy? correct answer: Temperature increases, entropy increases (direct) What is the relationship between atomic weight and entropy? correct answer: Heavier = increased entropy (direct) What happens to entropy when a substance is dissolved in another? correct answer: Entropy increases What is the relationship between moles of gas and entropy? correct answer: When moles of gas increase, entropy increases (direct) What does change in G measure? correct answer: The extent of the spontaneity of a process, and the useful energy available from it What is the relationship between work and spontaneous processes? correct answer: Spontaneous processes produce work What is the relationship between work and non-spontaneous processes? correct answer: Non-spontaneous processes require work What does -w mean? correct answer: Work is being produced - spontaneous What does a positive sign for w mean? correct answer: Work is required - non-spontaneous What is the relationship between free energy, enthalpy, and entropy? correct answer: Δ(system)=ΔH(system)-TΔS(system) Can a change be spontaneous in both directions? correct answer: No What is an extensive property? correct answer: Value depends on the amount of substance What does ΔG > 0 mean? correct answer: Non-spontaneous process - requires work What does ΔG < 0 mean? correct answer: Spontaneous process - produces work What does standard free energy of formation mean? ΔGo correct answer: The free energy change that occurs when 1 mole of a compound is made from its elements What is the standard free energy of formation for an element in its standard state? ΔGf correct answer: 0 What does reversing a reaction do to the standard free energy of