Bonding7

Get answer through fajan's rule

@ eureka

I know that but how will i compare Mgo to NaCl??Using charge density??But i dont know how to??

Na^+,K^+,Mg^{2+},Ba^{2+}

Now higher the charge greater is covalency=> \ Melting \ point \ order \ :Na^+,K^+>Mg^{2+},Ba^{2+}

Now if charge same..smaller the size greater the covalency,

\begin{matrix} We \ know \ size :K^+ >Na^+\\ => Covalent \ character \ : Na^+>K^+ \\ => Melting \ point \ :K+>Na^+ \\ => Max. \ melting \ point =KCl \end{matrix}

I hope its clear now...

I dont have the values...jsut did it by logic...anyways i will check now..

Ya..the values show opp trend...dont know why[7][7]

I think it has something to do with packing of the molecules in a lattice.

Yeah answer is also given as MgO but acc to Fajan it should be KCl..Now why??

thats teh real problem....i dont see anything wrong in my working....so how are we going to do in exam ???

we cant learn MP,BP and oher things of million compounds....there must be some logic...out of thousand other logics in inorganic

None of you think that it is related to packing of molecules?