General Princip...

Thermite is a mixture of iron oxide and :

The method of zone refining of metals is based on the principle of:

In which of the following isolations no reducing agent is required?

Zinc, cadmium and mercury are found in nature as sulphides. Values of standard reduction potentials for the half-reactions are : 

$$M^{2+}(aq)\, +\, 2e^{-}\,
\rightarrow\, M(s)$$ 

$$\begin{matrix}M & E^{\circ}\\ Zn &-\,0.76\,V \\ Cd & -\,0.40\,V \\ Hg & +\,0.79\,V\end{matrix}$$ . 

Which sulphides give element not oxide on roasting?

Froth flotation is a process of _____________.

Purification of alumina takes place by _________________.

The methods chiefly used for the extraction of lead and tin from their ores are respectively _________________.

Cryolite, $$Na_3AlF_6$$ is added to $$Al_2O_3$$ in Hall-Heroult process to ____ m.p. and to ___________ electrical conductivity.

Most abundant metal in earth crust is___________.

Which of the elements indicated by A, B, C and D is expected to be found in native state?