IB›IB Chemistry SL›Mind mapsS3.1 The periodic table: Classification of elementsIB Chemistry SL: Mind mapStudy pack PDFAlso for this subtopic:Revision notesFlashcardsSubtopic testCover factsLayoutPeriod = outer main energy levelGroup: same valence electronss, p, d, f blocks by sublevel fillingMetalloids on the staircase boundaryGroup 15, period 4: [Ar]3d104s24p3[\text{Ar}]3d^{10}4s^2 4p^3[Ar]3d104s24p3Trends acrossNuclear charge rises, shielding similarAtomic radius decreasesIonisation energy and electronegativity increaseDown a group: more shielding, radius risesIonic radiusCations smaller than atoms: level emptiedAnions larger than atoms: more repulsionIsoelectronic: radius falls as charge risesNaX+>MgX2+>AlX3+\ce{Na+} > \ce{Mg^2+} > \ce{Al^3+}NaX+>MgX2+>AlX3+Periodic tableclassifying elementsspdfGroups 1 and 172 Na+2 HX2O→2 NaOH+HX2\ce{2Na + 2H2O -> 2NaOH + H2}2Na+2HX2O2NaOH+HX2Group 1 reactivity increases downHalogens displace less reactive halidesClX2+2 BrX−→2 ClX−+BrX2\ce{Cl2 + 2Br- -> 2Cl- + Br2}ClX2+2BrX−2ClX−+BrX2Group 17 reactivity decreases downOxidesBasic: NaX2O\ce{Na2O}NaX2O, MgOAmphoteric: AlX2OX3\ce{Al2O3}AlX2OX3Acidic: SOX2\ce{SO2}SOX2, SOX3\ce{SO3}SOX3, PX4OX10\ce{P4O10}PX4OX10SOX3+HX2O→HX2SOX4\ce{SO3 + H2O -> H2SO4}SOX3+HX2OHX2SOX4Exam tipsOxidation state: sign first (+4)Ionic charge: number first (4+)Do not forget 3d¹⁰ in Ga to KrHalogen only oxidises halides below it