1- On the gravimetric determination of Ca2+ ! the most satisfactory form (being
nonhygroscopicl to be weighed is:
A. CaCO3     B. CaO          C. CaC2O4.H2O        D. CaC2O4
2. The following is not a form of "co-precipitation":
A. Occlusion.    B. Inclusion.     C. Post precipitation.     D. Surface adsorption.
3- For optimal precipitation process, requirements are:
A. High "relative super saturation".        B. High rate of "nucleation".
C. Formation of large number of fine crystals.    D. Formation of small number of large crystals.
4- During the formation of BaSO4 crystals! "non-isomorphic inclusion" may be caused by:
A. PbSO4      B. K2SO4       C. Ba(NO3)2       D. BaCl2
5- The most efficient method for treatment of occlusion is:
A. Washing.     B. Digestion     C. Reprecipitation     D. All are equivalent.