TD 1

• What are extensive properties?


  Depend on the amount of substance
• What are the intensive properties?

  doesnt depend on amount of substance and are not additive
• How to transform properties from extensive to intensive?

  dividing by moles
• What is the formula for heat capacity?

  C = q/ΔT
• What is the formula for specific heat capacity?

  heat capacity * 1/mass
• What is a reversible process?

  A process that occurs through an infinite number of equilibrium steps (ideal)
• What is the first law?

  Energy cannot be created or destroyed, only transferred. Internal energy is constant in an isolated system.
• What is the formula for internal energy?


  ΔE = q + w
• What is the formula for work in gases?

  W = -pV
• What is the formula for molar heat capacity at constant volume?

  Cv = (de/dT)v
• When is a gas ideal?

  Follows Pv=nRT , no interactions (only has kinetic energy) and internal energy depends on temperature
• What is the internal energy for an isothermal expansion (reversible)

  E = 0
• What is the formula for enthalpy?

  H = E + PV
• What is meyer's equation?

  Cp - Cv = R
• What is the equation linking V and T in adiabatic expansion?

  T1V1^(adiabatic coef -1) = T2V2^(adiabatic coef - 1)
• What are the conditions for standard state?

  1 bar and 298.15K
• Why are there variations in enthalpy?

  Intermolecular forces
• What are the intermolecular forces?

  Electrostatic interactions , van der waals , london , hydrogen bonding
• What are characteristics of London forces?


  very weak , depend on molar mass and the shape of molecules
• What is the formula for bond enthalpy?

  Sum of Bonds Broken + Sum of Bonds formed
• What is the formula for enthalpy of formation?

  H = sum of enthalpy of formation of products - Sum of enthalpy of formation of reactants
• What is Hess's Law?

  Total enthalpy in a chemical reaction is the same whether the reaction takes place in one or in several steps
• What is Kirchhoff's law?

  Hr = H(Ti) + Cpr * delta T