Question

3. Draw the Bom Haber Cycle and calculate the lattice energies for LiF, MgO, and CaC12 using the data provided in the table below. This can be done on a separate page if you are working off this template. AH (1/2 B.E.) Electon Affinity Ionization Sublimation AH EA Energy Ionic Compoud F 80 kJ/mol 328 kJ/mol Li 520 kJ/mol 155 kJ/mol LiF -594 kJ/mol 0 249.4 kJ/mol 141 kJ/mol (15) . Mg 738 kJ/mol (19) 148 kJ/mol MgO -601 kJ/mol -844 kJ/mol (2nd) 1451 kJ/mol (2nd) CI 121.7 kJ/mol 349 kJ/mol Ca 590 kJ/mol (15) 178 kJ/mol CaCl2 -796 kJ/mol 1145 kJ/mol (2nd) Energy 4. Arrange LiF, MgO, and CaCl, in order of increasing lattice energy values. 5. Explain the differences in lattice energies for the compounds above.

Answer 1

In question 3, the E.A (electron affinity) value for F, Cl should be in negative, but I have solved accordingly to the data provided in the table.

Page- Draw the Born- Habur cyce and Calculate the latice erergies forLiF, Mgo and Cact usna the data providad Bom Habar cyde applia Aatice enthal Herds law to Coleulate the Con paring o4 the ionic Compound to e enthalpy thetandard chmge ot torm ation enthalty Tused dements to make fam the gaseous LiF -594 Tmu AH (LiP) ST KT (mo AM(Li) DE (i) AME A(F) S20 KT/mot 328 kT Imaut Ди [Е) Li'lo+ +Fla) AMT-E S20 K0/mot AMEA LiGFl8) &0 Klmot F Lite) -tF() Lils) + Ca) AMI LiF (s) anLata(- 328 - S20 - 80- ISS + 59 E mot now - 489 kIm

Page-2 Mgitla)+oCe) (141 1mr) ДидеА TAat (149 s1 marl) AMEA Mg 2e t AMLY IE (1451 Km) AM IE73e kolmt) диЕ -? matalt ) AMub 148 Kolma Mt t013) Mgols) -6 0l ksimd AnLE 844-141- 249 4-145SE-98-48- Falmd ETImot 2487.4 Cadh ca) +20 t 2cl g) X2 (243-4) (2 x 349 JErlmt = 698 2 AMEA ET)mert cat 2 cl() LTImut Ca(a)2 ) Calg)+ cl() AMub(Te Catss+ g) ДИLЕ дир -796 kol m 4M (cach) 6 98 - 243.4 - 1148 - 590-138 - Caches) 796KT/m - 3 60 Eo mut