1) smallest = highest – why? outer electrons are in a shell closer to the nucleus outer electrons are in the same shell but pulled tighter by carbon’s six protons than boron’s five smallest = to the right – why? C B Al Na K _________ ________ ________ ________ ________ smallest largest largest = lowest – why? outer electrons are in a shell farther from the nucleus outer electrons are in the same shell but pulled tighter by aluminum’s thirteen protons than sodium’s eleven P Ge Ca Rb Sr Do question 2) _________ ________ ________ ________ ________ smallest largest

Cl [Ne] 3s2 3p5 Cl- [Ne] 3s2 3p6 Al O In I Cs Rb a) O2- O Br As 3) Cl [Ne] 3s2 3p5 Cl- [Ne] 3s2 3p6 Adding an electron to the p orbital increases the repulsion amongst the electrons in the p orbital making the anion larger than the parent atom Al O lower (and lefter) than O outer electrons are in a shell farther from the nucleus In I outer electrons are in the same shell but pulled tighter by iodine’s 53 protons than indium’s 49. Do question 4) Cs Rb 5) Ionization energy (energy required to remove an electron) increases up and right a) O2- O Br As

K Li N C Ca K As Si largest = right – why? 6) largest = right – why? outer electrons are in the same shell but pulled tightest by nitrogen’s seven protons thus harder to remove K Li C N _________ ________ ________ ________ smallest largest smallest = lowest – why? outer electrons are in a shell farther from the nucleus, thus easier to remove K Ca As Si Do question 7) _________ ________ ________ ________ smallest largest

a) Na b) O c) Na Mg P O a) S < O < F b) O c) Cl Do question 8) a) Na b) O c) Na Mg P O a) S < O < F 9) Removing an electron from fluorine or oxygen involves pulling it from the 2p orbital, which is harder than pulling if from the outer 3p orbital in sulfur. The electron removed from fluorine would be harder than that removed from oxygen because fluorine has two additional protons holding it. b) O Removing an electron from oxygen involves pulling it from the 2p orbital, which is harder than pulling if from the 3p orbital in sulfur or 4p orbital of selenium. c) Cl The electron to be pulled in is pulled into the 3p orbital for Cl, so there is less repulsion than an electron pulled into the 4p for Se or Br

g) Ne < F- < O2- < N3- d) O2- [He] 2s2 2p6 F- [He] 2s2 2p6 The electrons in O2- are pulled in by one less proton than those in F- so it is larger e) F < O < S outer electrons in S are in a shell farther from the nucleus so it is the largest. The electrons in O are pulled in by one less proton than those in F so O is larger f) S Removing an electron from Si, P, or Se involves pulling it from the 3p orbital, which is harder than pulling if from the 4p orbital in Se. Since S has more protons, the electron is held tighter and thus harder to remove. g) Ne < F- < O2- < N3- All have [He] 2s2 2p6 configuration The electrons in N3- are pulled in by the least number of protons . . . . largest the electrons in Ne are pulled in by the most number of protons . . . . smallest