Exam Level Born Haber Cycles
-
Upload
rockwell-kolby -
Category
Documents
-
view
42 -
download
2
description
Transcript of Exam Level Born Haber Cycles
Exam Level Born Haber Cycles
LOsTo understand the style of question asked for this unitTo improve the speed at which these questions are completed.
Enthalpies of Solution
LOsTo be able to calculate the enthalpy of solution
Define
1) The standard lattice enthalpy
2) The standard enthalpy of hydration
3) The standard enthalpy of solution
Dissolving
Similar looking diagram
OR Hess’s Law Triangle
Worked example
Ionic charge and radius
Ions with a higher charge have a higher enthalpy of hydration (more exothermic)
Ions with a smaller radius have a higher enthalpy of hydration (more exothermic)
Exam Questions
Entropy
Entropy is a measure of the number of different ways particles can be arranged.
It is a bit like how disordered or chaotic the system is.
Substances are more energetically stable as the system become more disordered.
Simple examples
Entropy tells us if a reaction will happen
ΔStotal = total entropy.
Spontaneous Reactions
For a reaction to happen spontaneously, the ΔG most be zero or negative.