Hess's Law

Shell Wood
Flashcards by Shell Wood, updated more than 1 year ago
Shell Wood
Created by Shell Wood about 8 years ago


A-Levels thermodynamics Flashcards on Hess's Law, created by Shell Wood on 05/26/2013.

Resource summary

Question Answer
Define Standard enthalpy change of formation The enthalpy change when one mole of a pure substance is formed from its elements in their normal physical states under RTP. (298K and 101.325 kPa)
Define Standard enthalpy change of combustion The enthalpy change when one mole of a pure substance is completely burnt in sufficient oxygen under rtp. (298K and 101.325 kPa)
ΔH means Total change in enthalpy
Define : Thermodynamics The science of energy conversion involving heat and other forms of energy especially work.
What is the 1st law of thermodynamics? Energy cannot be created nor destroyed
Standard enthalpy of formation. ΔH2 has to be reversed as does the value associated with this arrow.
Enthalpy of combustion ΔH [products] arrow has to be reverse as does the val
What are the conditions of RTP? 298 Kelvin 101.325 kPa
Define activation energy The minimum energy required to initiate a reaction.
How can the activation energy be reduced? How? Use a catalyst Lowers the Ea of a reaction by utilising different reaction pathways
Show full summary Hide full summary


MCAT Physics: Thermodynamics
Mike Nervo
Unit 5 Chemistry - Thermodynamics Definitions
Wannie Chisala
Edexcel AS Chemistry Unit 1
Vee Kirkland
Biochemistry 1
Physics 20 Final Exam Review Quiz
Fall Biology 3
Kate Kerr
Irene Binil
Molc Bio Exam 1 Flashcards
Year 11 - Heating processes
Fiona Heathcote