Chemical Thermodynamics — Chapter Summary

The part of the universe under

The part of the universe under study is called the system; everything else is the surroundings. Systems can be open (exchange matter and energy), clos

State functions like pressure

State functions like pressure, volume, temperature, and internal energy depend only on the initial and final states, not the path taken. Heat and work

Energy cannot be created or destroyed

Energy cannot be created or destroyed. The change in internal energy (ΔU) of a system equals heat absorbed (q) plus work done on the system (w): ΔU =

Enthalpy is defined as H =

Enthalpy is defined as H = U + PV. At constant pressure, the heat change (qₚ) equals the enthalpy change (ΔH). For exothermic reactions, ΔH is negativ

Standard enthalpy of formation (Δ_fH⁰)

Standard enthalpy of formation (Δ_fH⁰) is the heat change when 1 mole of a compound forms from its elements in their standard states. Enthalpy of comb