Galena (an ore) is partially oxidised by passing air through it at high temperature. After some time the passage of air stopped, but the heating is continued in a closed furnace such that the contents undergo self-reduction. The weight (in kg) of Pb produced per kg of `O_(2)` consumed is_ , `"Atomic weights in g mol"^(-1): O =16,S=32,Pb=207`

Galena (an ore) is partially oxidised by passing air through it at hig

1.	Galena (an ore) is partially oxidised by passing air through it at high temperature. After some time the passage of air stopped, but the heating is continued in a closed furnace such that the contents undergo self-reduction. The weight (in kg) of Pb produced per kg of `O_(2)` consumed is_ , `"Atomic weights in g mol"^(-1): O =16,S=32,Pb=207`
Answer» Ultimate reaction involed in the extraction of lead from galena is: `PbS+O_(2) to Pb+SO_(2)` Number of moles of Pb=Number of moles of oxygen `=(1000)/(32)` Mass of lead extracted `=((1000)/(32))xx"Molar mass of lead"` `=(1000)/(32)xx207=6470g` =6.74kg

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