CHEMISTRY- 7.9 Determining Enthalpies of
Reaction from Standard- STUDY GUIDE WITH 100%
CORRECT SOLUTIONS
ΔH - ✔✔Change in enthalpy for a chemical reaction.
Calorimetry - ✔✔Experimental method to measure heat changes.
Hess's Law - ✔✔Method to calculate ΔH using known reactions.
Standard State - ✔✔Reference conditions for measuring enthalpy changes.
Standard Enthalpy Change (ΔH°) - ✔✔ΔH when all substances are in standard
states.
Standard Enthalpy of Formation (ΔH_f°) - ✔✔Enthalpy change for forming 1
mol from elements.
1 bar - ✔✔Standard pressure close to 1 atm.
1 atm - ✔✔Standard atmospheric pressure for gases.
1 M - ✔✔Standard concentration for substances in solution.
Stable Form - ✔✔Most stable state of a substance at standard conditions.
, Pure Substance - ✔✔Substance without impurities at standard state.
Methane Formation - ✔✔ΔH_f° of methane is negative at 25 °C.
Graphite - ✔✔Most stable form of carbon at standard state.
kJ/mol - ✔✔Units for standard enthalpy of formation.
Negative ΔH_f° - ✔✔Indicates exothermic formation of compounds.
Sea Level Analogy - ✔✔Relative measurement for enthalpy changes.
Table 7.5 - ✔✔Lists standard enthalpies of formation for compounds.
Appendix IIB - ✔✔Contains complete list of standard enthalpies.
Chemical Equation - ✔✔Represents enthalpy of formation for 1 mol.
Temperature of Interest - ✔✔Often taken as 25 °C for standard states.
Constituent Elements - ✔✔Elements forming a compound in standard states.
Altitude Analogy - ✔✔Change in enthalpy compared to a defined zero.
Reaction from Standard- STUDY GUIDE WITH 100%
CORRECT SOLUTIONS
ΔH - ✔✔Change in enthalpy for a chemical reaction.
Calorimetry - ✔✔Experimental method to measure heat changes.
Hess's Law - ✔✔Method to calculate ΔH using known reactions.
Standard State - ✔✔Reference conditions for measuring enthalpy changes.
Standard Enthalpy Change (ΔH°) - ✔✔ΔH when all substances are in standard
states.
Standard Enthalpy of Formation (ΔH_f°) - ✔✔Enthalpy change for forming 1
mol from elements.
1 bar - ✔✔Standard pressure close to 1 atm.
1 atm - ✔✔Standard atmospheric pressure for gases.
1 M - ✔✔Standard concentration for substances in solution.
Stable Form - ✔✔Most stable state of a substance at standard conditions.
, Pure Substance - ✔✔Substance without impurities at standard state.
Methane Formation - ✔✔ΔH_f° of methane is negative at 25 °C.
Graphite - ✔✔Most stable form of carbon at standard state.
kJ/mol - ✔✔Units for standard enthalpy of formation.
Negative ΔH_f° - ✔✔Indicates exothermic formation of compounds.
Sea Level Analogy - ✔✔Relative measurement for enthalpy changes.
Table 7.5 - ✔✔Lists standard enthalpies of formation for compounds.
Appendix IIB - ✔✔Contains complete list of standard enthalpies.
Chemical Equation - ✔✔Represents enthalpy of formation for 1 mol.
Temperature of Interest - ✔✔Often taken as 25 °C for standard states.
Constituent Elements - ✔✔Elements forming a compound in standard states.
Altitude Analogy - ✔✔Change in enthalpy compared to a defined zero.
