electronic configuration ppt.ppt

1 1s 2 2s 2p 4s 3 3s 3p 3d 4 4p 4d 4f INCREASING ENERGY / DISTANCE FROM NUCLEUS THE ELECTRONIC CONFIGURATIONS OF THE FIRST 36 ELEMENTS CALCIUM As expected, the next electron pairs up to complete a filled 4s orbital. This explanation, using sub levels fits in with the position of potassium and calcium in the Periodic Table. All elements with an -s1 electronic configuration are in Group I and all with an -s2 configuration are in Group II. 1s2 2s2 2p6 3s2 3p6 4s2 ‘Aufbau’ Principle 1 1s 2 2s 2p 4s 3 3s 3p 3d 4 4p 4d 4f INCREASING ENERGY / DISTANCE FROM NUCLEUS THE ELECTRONIC CONFIGURATIONS OF THE FIRST 36 ELEMENTS SCANDIUM With the lower energy 4s orbital filled, the next electrons can now fill the 3d orbitals. There are five d orbitals. They are filled according to Hund’s Rule - BUT WATCH OUT FOR TWO SPECIAL CASES. 1s2 2s2 2p6 3s2 3p6 4s2 3d1 HUND’S RULE OF MAXIMUM MULTIPLICITY 1 1s 2 2s 2p 4s 3 3s 3p 3d 4 4p 4d 4f INCREASING ENERGY / DISTANCE FROM NUCLEUS THE ELECTRONIC CONFIGURATIONS OF THE FIRST 36 ELEMENTS TITANIUM 1s2 2s2 2p6 3s2 3p6 4s2 3d2 HUND’S RULE OF MAXIMUM MULTIPLICITY The 3d orbitals are filled according to Hund’s rule so the next electron doesn’t pair up but goes into an empty orbital in the same sub level. 1 1s 2 2s 2p 4s 3 3s 3p 3d 4 4p 4d 4f INCREASING ENERGY / DISTANCE FROM NUCLEUS THE ELECTRONIC CONFIGURATIONS OF THE FIRST 36 ELEMENTS VANADIUM The 3d orbitals are filled according to Hund’s rule so the next electron doesn’t pair up but goes into an empty orbital in the same sub level. 1s2 2s2 2p6 3s2 3p6 4s2 3d3 HUND’S RULE OF MAXIMUM MULTIPLICITY 1 1s 2 2s 2p 4s 3 3s 3p 3d 4 4p 4d 4f INCREASING ENERGY / DISTANCE FROM NUCLEUS THE ELECTRONIC CONFIGURATIONS OF THE FIRST 36 ELEMENTS CHROMIUM One would expect the configuration of chromium atoms to end in 4s2 3d4. To achieve a more stable arrangement of lower energy, one of the 4s electrons is promoted into the 3d to give six unpaired electrons with lower repulsion. 1s2 2s2 2p6 3s2 3p6 4s1 3d5 HUND