Focus 2 
http://bcs.whfreeman.com/webpub/chemistry/qmc2e/impact/qchem_impact2.html 
Focus 3
http://bcs.whfreeman.com/webpub/chemistry/qmc2e/impact/qchem_impact3.html 
Focus 5
http://bcs.whfreeman.com/webpub/chemistry/qmc2e/impact/qchem_impact5.html 
Focus 8
http://bcs.whfreeman.com/webpub/chemistry/qmc2e/impact/qchem_impact8.html 
Focus 9
http://bcs.whfreeman.com/webpub/chemistry/qmc2e/impact/qchem_impact9.html 
Focus 10
http://bcs.whfreeman.com/webpub/chemistry/qmc2e/impact/qchem_impact10.html 
Focus 12
http://bcs.whfreeman.com/webpub/chemistry/qmc2e/impact/qchem_impact12.html 
Focus 13
http://bcs.whfreeman.com/webpub/chemistry/qmc2e/impact/qchem_impact13.html 
Focus 14
http://bcs.whfreeman.com/webpub/chemistry/qmc2e/impact/qchem_impact14.html 
Focus 15
http://bcs.whfreeman.com/webpub/chemistry/qmc2e/impact/qchem_impact15.html 
Focus 16
http://bcs.whfreeman.com/webpub/chemistry/qmc2e/impact/qchem_impact16.html 
Focus 17
http://bcs.whfreeman.com/webpub/chemistry/qmc2e/impact/qchem_impact17.html 
Focus 19
http://bcs.whfreeman.com/webpub/chemistry/qmc2e/impact/qchem_impact19.html  
Focus 20
http://bcs.whfreeman.com/webpub/chemistry/qmc2e/impact/qchem_impact20.html