Ncert Solutions Chemistry Class 12th

Misch metal consists of Lanthanide metal (? 95%) and iron (? 5%) and traces of S, C, Ca and Al.

The chemical structure shown is 5-Amino-4- (hydroxymethyl)-2-nitrobenzene carbaldehyde.

(i) Ca (OH)? is used in white wash.
(ii) Plaster of paris is used in making of molds for plaster statues.
(iii) NaCl is used in preparation of washing soda.
(iv) A suspension of Mg (OH)? in water is used in medicine as an antacid under name of milk of magnesia.

(I) Lucas reagent → Only ZnCl? /Conc. HCl
(II) Dumas method → CuO/Δ
(III) Kjeldahl's method → Conc. H? SO? /Δ
(IV) Heinsberg reagent → C? H? SO? Cl/ aq. NaOH

Zn, Cd&Hg are purified by fractional distillation process.

In the ccp lattice of oxide ions effective number of O? ² ions = 8 *? + 6 * ½ = 4
In the ccp lattice,
No. of octahedral voids = 4
No. of tetrahedral voids = 8
Given M? atoms occupies 50% of octahedral voids and M? atoms occupies 12.5 of tetrahedral voids
No. of M? metal atoms = 4 *? /? = 2
No. of M? metal atoms = 8 * ¹²·? /? = 1
∴ Formula of the compound = (M? )? (M? )O?
∴ Oxidation states of metals M? & M? respectively are +2 and +4 .