[{"data":1,"prerenderedAt":117},["ShallowReactive",2],{"cheatsheet-periodic-properties-and-trends":3},{"sheet":4},{"sheetSlug":5,"topicSlugs":6,"primaryTopic":7,"title":8,"subtitle":9,"sections":10},"periodic-properties-and-trends",[5],13,"Periodic Properties & Trends","Effective nuclear charge and the radius, ionization energy, electron affinity, electronegativity, and ionic-size trends.",[11,23,31,39,47,55,63,76,84,108],{"heading":12,"kind":13,"items":14},"Effective nuclear charge","rules",[15],{"ref":16,"mode":19,"provenance":20,"text":21,"source_hash":22},{"type":17,"topic":7,"id":18,"field":17},"rule","PT-R002","transform","original","Z_eff = protons minus shielding by core and same-shell electrons (core shields well, same-shell poorly). It rises left-to-right across a period and drives the radius and IE trends.","e300337b7632762d477eccd373ed2a6252adc59f041fb2799044ce91ce9581d3",{"heading":24,"kind":13,"items":25},"Atomic radius",[26],{"ref":27,"mode":19,"provenance":20,"text":29,"source_hash":30},{"type":17,"topic":7,"id":28,"field":17},"PT-R001","Radius increases down a group (higher n shell) and decreases across a period (higher Z_eff pulls the same-shell valence electrons in tighter).","8417196957821d6db6b16e4740d99d08bc592e2434ad77a69c1556b2ac4703f3",{"heading":32,"kind":13,"items":33},"Ionization energy",[34],{"ref":35,"mode":19,"provenance":20,"text":37,"source_hash":38},{"type":17,"topic":7,"id":36,"field":17},"PT-R003","IE₁ rises across a period, falls down a group. Two dips: Be → B (B loses a higher-energy 2p) and N → O (O loses a paired 2p, restoring half-filled stability).","0f5f890a38d9d3759308004e310484238fae893ebba1243a3ce560f710c65858",{"heading":40,"kind":13,"items":41},"Successive IE jump",[42],{"ref":43,"mode":19,"provenance":20,"text":45,"source_hash":46},{"type":17,"topic":7,"id":44,"field":17},"PT-R004","IE₁ \u003C IE₂ \u003C IE₃ … always. A sharp jump appears when the next electron removed is a core electron: a jump after IEₙ means n valence electrons.","806ac5f350ebe48a4f58600b44af1784bc10086733d099474004b3b375110737",{"heading":48,"kind":13,"items":49},"Electron affinity",[50],{"ref":51,"mode":19,"provenance":20,"text":53,"source_hash":54},{"type":17,"topic":7,"id":52,"field":17},"PT-R006","EA generally becomes more negative across a period. Exceptions: groups 2, 15, 18. Cl has the most negative EA (adding an electron to tiny F is destabilized by repulsion).","29dbea338515a1aaf9e3fd36acc044da767c987d96f24832559a030297ccf526",{"heading":56,"kind":13,"items":57},"Electronegativity",[58],{"ref":59,"mode":19,"provenance":20,"text":61,"source_hash":62},{"type":17,"topic":7,"id":60,"field":17},"PT-R005","Electronegativity (Pauling) increases up and to the right; F is highest (χ = 3.98). Use it qualitatively, for ranking and comparison.","747b4908f2e52e5f84c16fe6f586778acfd0967c85be148c7f8053c83892c34b",{"heading":64,"kind":13,"items":65},"Ionic radius",[66,71],{"ref":67,"mode":19,"provenance":20,"text":69,"source_hash":70},{"type":17,"topic":7,"id":68,"field":17},"PT-R007","A cation is smaller than its atom (fewer electrons, higher Z_eff each; main-group cations expose the inner shell).","d66e4abdfa0d3c477b08c4f5e338ba39288a63d4029059f240481e719eb003f9",{"ref":72,"mode":19,"provenance":20,"text":74,"source_hash":75},{"type":17,"topic":7,"id":73,"field":17},"PT-R008","An anion is larger than its atom (added electrons raise repulsion, lower Z_eff each). S: 104 → S²⁻ 170 pm.","de7f08e6c91cfb35197e7cb2704842862351d08832125665680e8e35abb7b81e",{"heading":77,"kind":13,"items":78},"Isoelectronic series",[79],{"ref":80,"mode":19,"provenance":20,"text":82,"source_hash":83},{"type":17,"topic":7,"id":81,"field":17},"PT-R009","Same electron count = isoelectronic. Radius shrinks as Z rises. 10-e⁻ set: N³⁻ > O²⁻ > F⁻ > Ne > Na⁺ > Mg²⁺ > Al³⁺.","b27c41dd03765692fb4aaa91b7925e2e42bbdf4988d4205bc1305e33844455f2",{"heading":85,"kind":86,"columns":87,"items":90},"Bond character from ΔEN","data",[88,89],"ΔEN","Bond type",[91,105],{"ref":92,"mode":19,"provenance":20,"rows":94,"source_hash":104},{"type":17,"topic":7,"id":93,"field":17},"PT-R011",[95,98,101],[96,97],"\u003C ~0.4","nonpolar covalent",[99,100],"~0.4 to \u003C~1.7","polar covalent",[102,103],"≥ ~1.7","ionic","d90093b41b04254ab9bbd18bf34a115b606209924ca245b4885997bb95b7f1ea",{"ref":106,"mode":19,"provenance":20,"text":107,"source_hash":104},{"type":17,"topic":7,"id":93,"field":17},"Rough guide only: the thresholds are heuristic, and some borderline cases go by chemistry (e.g. NaH, ΔEN ≈ 1.2, is treated as ionic).",{"heading":109,"kind":13,"items":110},"Group similarity",[111],{"ref":112,"mode":19,"provenance":114,"text":115,"source_hash":116},{"type":17,"topic":7,"id":113,"field":17},"PT-R012","owned_workbook","Same-group elements share a valence configuration (Ca, Sr, Ba are ns²) so they share reactivity, oxidation states, and bonding. Diagonal likenesses (Be↔Al, Li↔Mg) are secondary.","571a1239de182732f9e5b150b3e68b2c1b9cbe90bf0a0b69ca1cdc86a288ba5d",1787246033253]