80 likes | 197 Views
TechDis Accessibility Essentials 3: Creating Accessible Presentations. This presentation on ‘ The Born-Haber Cycle ’ highlights how complex content can be displayed in a logical user friendly manner. Using annotations and animations.
E N D
TechDis Accessibility Essentials 3: Creating Accessible Presentations This presentation on ‘The Born-Haber Cycle’ highlights how complex content can be displayed in a logical user friendly manner. Using annotations and animations. Navigate through the slides sequentially. The Notes section provides textual exemplification of the graphical information.
BORN-HABER CYCLE FOR SODIUM CHLORIDE • For an ionic compound the lattice enthalpy is the heat energy released when one mole of solid in its standard state is formed from its ions in the gaseous state. • This value cannot be determined directly and so we make use of changes for which data are available and link them together with an enthalpy cycle. • This enthalpy cycle is based on the formation of the compound from its elements in their standard states.
H= +107kJmol-1 Atomisation of Sodium Na(g) + 1/2 Cl2(g) Na(s) + 1/2 Cl2(g)
H = +121kJmol-1 Atomisation of Chlorine Na(g) + Cl(g) Na(g) + 1/2 Cl2(g)0 Na(s) + 1/2 Cl2(g)
H = +502kJmol-1 + First Ionisation of Sodium Na+(g) + Cl(g) e- e- e- e- e- e- e- e- e- e- e- Na(g) + Cl(g) Na(g) + 1/2 Cl2(g) Na(s) + 1/2 Cl2(g)
H = -355kJmol-1 - First Electron Affinity of Chlorine Na+(g) + Cl(g) Na+(g) + Cl-(g) Na(g) + Cl(g) e- Na(g) + 1/2 Cl2(g) Na(g) + 1/2 Cl2(g) Na(g) + 1/2 Cl2(g) Na(s) + 1/2 Cl2(g)
+ + + + - - - - - H = -351kJmol-1 Formation of Sodium Chloride Na+(g) + Cl(g) Na+(g) + Cl-(g) Na(g) + Cl(g) Na(g) + 1/2 Cl2(g) Na(g) + 1/2 Cl2(g) Na(g) + 1/2 Cl2(g) Na(s) + 1/2 Cl2(g) NaCl(s)
+ + + + - - - - - H = -726kJmol-1 Lattice Enthalpy for Sodium Chloride Na+(g) + Cl(g) Na+(g) + Cl-(g) Na(g) + Cl(g) Na(g) + 1/2 Cl2(g) Na(g) + 1/2 Cl2(g) Na(g) + 1/2 Cl2(g) Na(s) + 1/2 Cl2(g) NaCl(s)