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Predict the formulae of thestablebinary compoundsthat would be formedbythe followingpairs of elements (a) silicon andoxygen (b)aluminium andbromine( c )calcium and iodine (d)element 114 and fluorine (e )element 120 and oxygen. |
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Answer» Solution :(a) Silicon belongsto GROUP 14. it has four valenceelectrons and hence its valence= 4 Oxygen belong to group 16. It has six electrons in thevalence shell andhenceits valence =8-6 =2 . Therefore theformula of silicon oxide= `SiO_(2)`. ( b)Aluminium belongs to group 13. It has three electron in the valenceshelland henceits valence =3. Brominebelongs to group 17. It hassevenelectrons in thevalence shell and hence its valence =8-7 =1 Thereforeformula of aluminium bromide= `AIBr_(3)` (c ) Calcium belongsto group 2. Ithas two -electrons in the valenceshelland henceits valence=2 .Iodine belongs to group 17. Ithas seven valence electrons and hence its valence =8-7=1. Thereforeformula of calcium iodic= `Cal_(2)` (d )In the7th period the 4TH transition seriesends at element with Z =112, thereforefilingof 7p- subshell willbegin withelement Z=113 .Henceelement with Z= 114 will have two electrons in 7p- orbitals andtwoelectrons in 7 s-orbital .In otherwordsthe element Z= 114 willlie ingroup 14 and henceits valence =4 fluorinebelongsto group 17 withsevenvalenceelectrons and henceitsvalence =8-7=1 Thereforeformulaof compoundformedby element114 andfluorineis `MF_(4)` where M representsthe element (e) The7thperiodends atelement with Z= 118. Thereforefillingof 8th shell i.e., 8 s-orbital willbegin with element Z= 119 andconsequently with Z= 120will belongto group 2 andits valencewill be=2 Oxygen belongsto group 16 withsixvalenceelectrons and henceits valence=8-6=2. Thereforeformula of compound formedby element Z= 120and oxygen will be MOwhere M respresent element. |
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