Question

(iv) When an impurity is introduced during the development of crystal lattice of a
precipitate the
phenomenon is called
(a) post precipitation
()
6) co-precipitation
(c) supersaturation
(d) complex formation
(v) Digestion has no effect when the ppt. is
(a) colloidal
(b) gelatinous (c) slimy (d) crystalline
(vi) Which Whatman filter paper is used for filtering the precipitate of BaSO4 ?
(a) No. 39
(b) No. 40 (c) No. 41
(d) No. 42
(vii) Thermogravimetric analysis is not concerned with
(a) time (b) temperature (weight (d) reagent of precipitation​

Answer 1

Answer:

Surface adsorption :- Impurities are adsorption on the surface of ppt. Post precipitation :- It is the precipitation that occur as a layer upon the already formed precipitate.An occlusion occurs when an adsorbed impurity gets physically trapped inside the crystal as it grows.Post precipitation is a kind of precipitation where the precipitation of the undesirable compound occurs after the formation of the precipitate of the desired compound. ... It is the precipitation that transpires as a layer upon the already formed precipitate.