Aluminothermic process is used for the extraction of metals, whose oxides are:
(b) not easily reduced by carbon
(c) not easily reduced by hydrogen
(d) strongly basic
(b) Alumino-thermic process is commonly used for those metals which have very high m.pt. and are to be extracted from their oxides and their reduction with carbon is not satisfactory.
Sulphide ores are common for the metals:
(a) Ag, Cu and Pb
(b) Ag, Cu and Sn
(c) Ag, Mg and Pb
(d) Al, Cu and Pb
(a) Metals having high polarising power (Zeff) exist in ore with anions having high polarisibility
Ag, Cu, Pb Sulphide ores (Ag2S, CuFeS2, Pbs)
Sn Oxide ore (SnO2)
Mg Sea water and dolomite (CaCO3, MgCO3)
Al Oxide ore (Al2O3.2H2O)
Which element occurs freely in nature?
(b) Sulphur occurs in native state while iodine, phosphorus and magnesium are found in combined state.