CBSE
Which of the following is philosopher's wool ?
ZnO
HgO
Ag2O
CuO
For which element the inertness of the electron pair will not be observed?
Sn
Fe
Pb
In
When H2S gas is passed in a metal sulphate solution in presence of NH4OH, a white precipitate is produced. The metal is identified as:
Zn
Fe
Pb
Hg
Which one is malachite from the following?
Cu(OH)2
Fe3O4
CuCO3.Cu(OH)2
CuFeS2
Composition of azurite mineral is
CuCO3.CuO
Cu(HCO3)2.Cu(OH)2
2CuCO3.Cu(OH)2
CuCO3.2Cu(OH)2
84Rn219 is a member of actinium series. The other member of this series is-
89Ac225
90Th232
15P35
92U235
Anhydrous ferric chloride is prepared by:
dissoving Fe(OH)3 in concentrated HCl
dissolving Fe(OH)3 in dilute HCl
passing dry HCl overheated iron scrap
passing dry Cl2 gas overheated iron scrap