Warm Up Write the electron configuration for F. Then draw the orbital diagram.

Bohr’s Model Shows the total number of electrons in each energy level (shell). Notice the electrons are paired, just as they are in the orbital diagram. bohr_atom.gif

Relation between shell and subshell First shell: 1s Second shell: 2s and 2p Third shell: 3s, 3p and 3d Fourth shell: 4s, 4p, 4d and 4f Predict – 8th shell… 8 subshells! The number of subshells in equal to the shell (period) number!

Total electrons in each shell First shell: 1s has 2 Second shell: 2s has 2 and 2p has 6 = 8 Third shell: 3s has 2, 3p has 6, 3d has 10 = 18 Fourth shell: 4s has 2, 4p has 6, 4d has 10, 4f has 14 = 32

Draw Bohr’s model for… H Predict the change for Li Why is the electron green? Because it is in an s orbital! (outlined in green)

Draw Bohr’s model for… H Li Predict the change for Na 1s22s1

Draw Bohr’s model for… H Li Na Predict the change for K 1s22s22p63s1 We are taking our orbital diagram and cutting apart the separate shells and then bending them into a circle!

Draw Bohr’s model for… H Li Na K What change did you notice in the size of the atom? Size increased as more energy levels (shells) were added! 1s22s22p63s23p64s1

Draw Bohr’s Model for… Li Be B C N O F Ne Predict the change that will occur as we go across the second period. What occurred at the particle level across this period? Added an additional electron AND an additional proton.

Atomic Radius Trend Across a period, the atomic radius decreases due to the increased effective nuclear charge. There are more protons in the nucleus to attract and pull in the electrons bgrn1626l.jpg 650px‑AtomicRadius.png

Down a family, the atomic radius increases, due to the additional energy levels (shells) 650px‑AtomicRadius.png

Research Groups of 1 to 4 Research either Make a claim Electronegativity Electron affinity Ionization energy Make a claim How does the term relate to atomic radius trend Give your evidence Insert pictures of your findings Explain your reasoning This is where your VOICE comes into play Make a video of your claim, evidence and reasoning using educreations.