Lecture 01

• What is thermodynamics?

  Physical science of energy and matter
• How is thermodynamics described?

  By three laws of thermodynamics
• What does thermodynamics describe?

  Systems, not individual atoms or molecules
• How does thermodynamics help in chemical reactions?

  Predicts energy changes in reactions
• What defines a thermodynamic system?

  One with defined boundaries
• How are thermodynamic systems separated from surroundings?

  By a boundary
• What are the three types of thermodynamic systems?

  Open, closed, and isolated systems

  
• What is an open system?

  Exchanges heat, work, and matter
• What is a closed system?

  Exchanges heat and work, not matter
• What is an isolated system?

  Does not exchange heat, work, or matter
• How can the state of a thermodynamic system be defined?

  By two thermodynamic properties
• What are examples of thermodynamic properties?

  Pressure (P), temperature (T), and volume (V)
• What do thermodynamic properties depend on?

  Current state of the system
• What is a key characteristic of changes in thermodynamic properties?

  Depends only on values of A and B
• What happens to thermodynamic properties when returning to the initial state?

  No associated change in that property
• How do non-thermodynamic properties behave?

  Values depend on the path followed
• What is the Ideal Gas Equation?

  pV = nRT
• What does the Ideal Gas Equation assume?

  Gaseous atoms are point masses
• What is the value of the Ideal Gas constant R?

  0.082 L mol−1 K−1
• What is heat (q) in thermodynamics?

  Exchange of energy by thermal interactions
• What is work (ω) in thermodynamics?

  Exchange of energy by non-thermal interactions
• How can heat capacity (c) be expressed?

  As a function of moles or grams
• What is molar heat capacity (c_m)?

  Energy to raise 1 mol by 1 K
• What is specific heat capacity (c_s)?

  Energy to raise 1 g by 1 K
• How is heat energy (q) calculated?

  q = m * c_s * ΔT

  
• What does energy describe in thermodynamics?

  Amount of work done by force
• What does the First Law of Thermodynamics state?

  Internal energy is total energy of system
• What does internal energy depend on?

  Energy of all constituents of the system
• How is internal energy (U) calculated?

  U = heat energy + work
• What is chemical energy?

  Energy stored in molecules by chemical bonds
• What is bond energy?

  Energy stored in a chemical bond
• What happens during chemical reactions regarding energy?

  Bonds are broken and formed
• What is enthalpy of reaction (ΔH)?

  Overall energy change for a chemical reaction

  
• How are reactions classified based on enthalpy?

  As endothermic or exothermic

  
• What are the characteristics of exothermic reactions?

  • Energy of bonds formed > energy of bonds broken
  • Energy is released to surroundings
  • ΔH < 0 kJ mol^-1
• What are the characteristics of endothermic reactions?

  • Energy of bonds formed < energy of bonds broken
  • Energy is absorbed from surroundings
  • ΔH > 0 kJ mol^-1
• What is the relationship between exothermic reactions and spontaneity?

  Most exothermic reactions are spontaneous
• What is entropy (S)?

  Measure of disorder in a thermodynamic system
• What does the second law of thermodynamics state?

  Spontaneous processes increase disorder and entropy
• Are all processes with increased entropy spontaneous?

  No, not all are spontaneous