[lelouch]

Obtaining zinc from the ore consists of 54.0% of the metal sulfide and silica impurities, is made to calcine the ore and reducing the oxide formed with an initial amount of carbono.Para x 1.00 ³ 10 kg of ore, calculate:
1. the volume of air, measured at STP, necessary to complete the roasting, knowing that should be employed 40.0% more than the oxidation mixture;
2nd mass of zinc obtained, considering that the reduction step is a loss of 10.0% metal;
3. the mass of coke, containing 90.0% carbon, used in the reduction of all the zinc oxide formed, taking into account the need for an excess of 50.0% carbon.

[Hunter2]

First get the equations for the rosting and reduction process.

Get the molecular weights for the products and educts.

With the given amounts corrected with the percentage values you can calculate the amounts of the needed or optained compounds. Convert to mole!!!