100 kg of roasted zinc ore with composition: 66% ZnO, 3% ZnS, 10% PBO, 14% Fe;Os, 1% Al;Os, 6% SIO; is reduced in a horizontal retort furnace with 45 kg coke having 90% C and 10% SIO2. In the furnace 91% of Zno is reduced to Zn 100% of Pbo is reduced to Pb 75 % of Fe,O, is reduced to Fe, 25 % of Fe,O, is reduced to Feo Neglect the vaporization of Pb and Fe and accept that they will not reoxidize. 1. Determine the weight of zinc and the percentage of zinc gained from the ore. 2. Determine the theoretical weight of C required for the reduction of Zno and the percentage of the excess C. 3. Determine the weight and the percentage of the residual material in the retort furnace after the removal of zinc vapor.

Consider a modification to the Hall-Heroult process for aluminum production, where we keep things the same but replace the carbon electrode by something inert. The original process requires three electrons to produce one atom of Al metal and is: (1/2) Al½O3 + (3/4) C → Al + (3/4) CO2 Suppose that the new process also requires three electrons and is (1/2) Al,O; → Al + (3/4) O2 If the energy, E, produced from the reaction C + O2 → CO2 is 4.08 eV per carbon atom, how much would the voltage need to be increased in order produce aluminum assuming that the energy from the oxidation of carbon to carbon dioxide is replaced by electrical energy in the process?

10 Calculate the oxidation number of: Cl in Ba(CIO;)2 a b S in S,O,2

Calculate the amperage required to deposit 41.7 grams of nickel (AW=58.69) from a solution of NiCl2(aq) in 2.26 hours

6. Balance the following reaction in basic solution (add water or OH- as needed): Cr3+ (aq) + C1O4 (aq) Cr₂O72-(aq) + CIO-(aq)

Determine the corrosion rate ( mpy ) of steel corresponding to 1µA / cm? of current. Following is the composition of alloys. Cr = 21%, density = 7.1 g/ cm', At.wt. = 52.01 g /mol, number of electron = 1 Ni = 8%, density = 8.9 g/ cm', At.wt. = 58.68 g /mol, number of electron = 2 Fe = 70%, density = 7.86 g/ cm', At.wt. = 55.85 g /mol, number of electron = 2 Note : Faradays constant = 96500 coulombs per mole of electrons. C= constant which includes F and any other conversion factor for unites, for instance, C = 0.129 when corrosion rate is in mpy.

In the Hall - Heroult process, aluminum is produced by the electrolysis of molten Al₂O3(0). The half reactions are C(s) +20²- (aq) → CO₂(g) + 4e¯ Al³+ +3e → Al(s) (aq) The mass of Al(s) produced for 2.00 kg of C(s) consumed is (round to the nearest kg) 6.00 kg 1.69 kg 2.45 kg 3.00 kg

8. For the oxidation-reduction reaction: S406 (aq) + Cr(aq) Cr (aq) + S2032 (aq), the appropriate half reactions are: Cr+ + e Cr+ E = -0.50 V. %3D S.O+ 2e- 2S2O3 V - E° = 0.17 -> Balance the redox equation and calculate E° and K (at 25 °C.

2. Lead (II) sulfide is the principle source of lead metal. To obtain the metal, the sulfide is first heated in air to produce PbO. PbS + 3/20,e - PbO + SO2) AH = -415.4 kJ (s) (8)7 The oxide is then reduced to the metal with carbon. PbO + C - Pb + CO (s) Calculate AH for the reaction of one mole of PbS with oxygen and carbon, forming lead, sulfur AH =+108,5 kJ (s) dioxide and carbon monoxide.

What is the percentage of Fe in an iron ore of 0.5 g of the ore,after solution, in acid and complete reduction of the iron, requires 25.50 ml KMnO4(1 ml is equivalent to 0.0126 g H2C2O4.2H2O) for oxidation?