Predict the formula of thestablebinarycompoundsthat wouldbe formedby theconbination ofthe followingpairsof elements ( a)Lithium and oxygen( b)Magnesium andnitrogen( c ) Aluminiumand iodine ( d ) Silicon and oxygen( e)Phosphorus andfluorine( f) Element71 and fluorine .

Predict the formula of thestablebinarycompoundsthat wouldbe formedby t

1.	Predict the formula of thestablebinarycompoundsthat wouldbe formedby theconbination ofthe followingpairsof elements ( a)Lithium and oxygen( b)Magnesium andnitrogen( c ) Aluminiumand iodine ( d ) Silicon and oxygen( e)Phosphorus andfluorine( f) Element71 and fluorine .
Answer» Solution :(a) Lithium is analkalimetal ( Group 1). It has only oneelectron in thevalenceshell,thereforeitsvalenceis 1. Oxygen is agroup16 element witha valenceof 2. Therefore. Formulaof the compound formedwould be `Li_(2)O` ( lithium oxide) . ( b)Magnesium is an alkaline earthmetal ( group 2) and hencehas avalenceof 2. Nitrogen is agroup 15 ELEMENTWITH avalenceof 8-5 =3.Thus theformulaof the compoundformedwould be`Mg_(3)N_(2)` (magnesiumnitride ) ( c) ALUMINIUMIS group 13 elementwith a valenceof 3 whileiodineis ahalogen( group 17)with avalenceof 1. Thereforethe formula of thecompoundformedwould be `A1I_(3)` ( aluminium iodine ). ( d)Silicon is agroup 14 elementwith avalenceof 4 whileoxygenis a group 16 elementwith avalenceof 2 . Hencethe formulaof the compound formedis `SiO_(2)` ( silicondioxide) ( e)Phosphorus is a group 15 elementwitha valenceof 3 or 5whilefluorine isa group 17 element witha valence of 1. Hencethe formula71 is alanthanoidcalledlutetium (LU). Itscommonvalenceis 3. Fluorineis agroup 17 ( halogen )elementwith avalence of1. Thereforethe formulaof THECOMPOUND formedwould be `LuF_(3)` ( lutetiumfluoride).