The principal ore of lead isA. galenaB. anglesiteC. cerussiteD. None o

1.	The principal ore of lead isA. galenaB. anglesiteC. cerussiteD. None of these.
Answer» Correct Answer - A Galena, natural lead `(II)` sulphide, `PbS`, is the principal ore of lead. It is a heavy crystalline mineral of metallic appearance. It is use as a semiconductor in crystal rectifiers. Anglesite `(PbSO_(4))` and cerussite `(PbCO_(3))` are less important ores of lead. There are two methods of extracting the element : (i) Roast in air to give `PbO` and then reduce with coke or `CO` in a blast furnace: `PbS+3O_(2)overset(Delta)rarrSO_(2)+2PbOoverset(+C)rarr2Pb(l)+CO_(2)(g)` (ii) `Pbs` is partially oxidized by heating and blowing air through it. After sometime, the air is turned off and heating is continued, and the mixture undergoes self-reduction. `3PbSunderset("Air")overset(Delta)rarrPbS+2PbOunderset("Without air")overset(Delta)rarr3Pb(l)+SO_(2)(g)`

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The principal ore of lead isA. galenaB. anglesiteC. cerussiteD. None of these.

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