UNIT- Choose the correct answer: . c) both covalent crystals . b) AB number of A ions = = = N c number of B ions = = = N f simplest formula AB . b) : if number of close packed atoms =N; then, The number of Tetrahedral holes formed = 2N number of Octahedral holes formed = N therefore N:2N = : .
c) molecular solid lattice points are occupied by CO molecules . a) Both assertion and reason are true and reason is the correct explanation of assertion. . c) and CaF has cubical close packed arrangement Ca + ions are in face centered cubic arrangement, each Ca + ions is surrounded by F − ions and each F − ion is surrounded by Ca + ions.
Therefore coordination number of Ca + is and of F − is . b) . × in BCC unit cell, atoms ≡ unit cell Number of atoms in 8g of element is , Number of moles = g g mol mol mole contains atoms . mole contains atoms 1unit cell atoms × unit cells - - - - .
d) M N if the total number of M atoms is n, then the number of tetrahedral voids =2n given that rd of tetrahedral voids are occupied i.e., × n are occupied by N atoms ∴ ⇒ ⇒ M:N M N n n : : : . c) r r A C + it is in the range of . – . , hence the coordination number of each ion is .
d) × pm r r r r r int Cs Cl