Amongthe elementB ,A1 , C and Si(i) Whichelementhas thehighestfirstionisationenthalpy? (ii)Whichelement has the mostmetalliccharacter? Justifyyouranswer in theeach case .

Amongthe elementB ,A1 , C and Si(i) Whichelementhas thehighestfirstion

1.	Amongthe elementB ,A1 , C and Si(i) Whichelementhas thehighestfirstionisationenthalpy? (ii)Whichelement has the mostmetalliccharacter? Justifyyouranswer in theeach case .
Answer» Solution :ARRANGING theelements B, A1 , C and Siintodifferentgroupsand periods in orderof theirincreasingatomicnumberwe have , `{:(" Group " to ,,13,,14),("Period" 2,,B,,C),("Group" 3,,A1,,SI):}` (i) Sinceionizationenthalpyincreasesalonga PERIODAND decreasesdowna groupthereforeC has thehighestfirstionizationenthalpy (ii) Sincemetalliccharacterincreasesdowna groupanddecreasesalonga periodthereforeA1 isthe mostmetallicelement .