Consider the following statements and arrange in the order of true/false as given in the codes. S_1: One type of units cells are possible for the crystallaographic dimensions as a=b ne c and alpha=beta=gamma=90^@. S_2: In the configuration shonw the size of the smallest circle is (2/sqrt3-1) times the size of the biggest circles. S_3:Number of next neighbours of Cs^+ ion in CsCl structure is 6 Cs^+ ions S_4: A crystal has A ions at the cube corners and B ions at the edge centres.The coordination number of A and B are respectively 6 and 2

Consider the following statements and arrange in the order of true/fal

1.	Consider the following statements and arrange in the order of true/false as given in the codes. S_1: One type of units cells are possible for the crystallaographic dimensions as a=b ne c and alpha=beta=gamma=90^@. S_2: In the configuration shonw the size of the smallest circle is (2/sqrt3-1) times the size of the biggest circles. S_3:Number of next neighbours of Cs^+ ion in CsCl structure is 6 Cs^+ ions S_4: A crystal has A ions at the cube corners and B ions at the edge centres.The coordination number of A and B are respectively 6 and 2
Answer» TTTT FFTT FTFT FFFF Solution :`S_1`:For the crystallaographic dimensions as `a=bnec` and `alpha=beta=gamma=90^@` simple & Body centered unit cells are possible. `S_2`:Acc. To the diagram two DIFFERENT triangles can be observed `Rto` radius of BIGGEST circle `r_(1)to` radius of smaller circle `r to` radius of smallest circle Using pythagoras `R^2 +r^2 +2Rr=R^2+R^2(4+2-4sqrt2)+r^2-2(2sqrt2)Rr` `R+2r=R+R(6-4sqrt2)-(4-2sqrt2)r` `(6-2sqrt2)r=R(6-4sqrt2)r/R=(6-4sqrt2)/(6-2sqrt2)` Size RATIO `=r^2/R^2=((6-4sqrt2)/(6-2sqrt2))^2` For point a (`Cs^(+)` ion) we have number of next neighbours of `Cs^(+)` ion in CsCl structure is `6Cs^(+)` ions, i.e. 1a,A2,a3,a4,a5,a6 `S_4:("C.N. of cation")/("C.N. of anion")=("charge of cation")/("charge of anion")=3/1=3` Now Xo-ordination no of A is shown so of B is 2.