Heavy metal sulfides like CdS and PbS are often significant components of mine tailings (the piles of waste and low-grade ores discarded by a mining operation). While these sulfides are quite insoluble in water (Ksp of CdS = 1 E -27, Ksp of PbS = 3 E -28), over the years rainwater and snowmelt can slowly dissolve small amounts of these heavy metals, washing them into streams and other natural waters. If these mine tailings are located in an area that is impacted by acid rain, would you expect heavy metal dissolution into natural waters to increase or decrease? Use chemical reactions to justify your answer.

Consider the balanced reaction: 2Cr3+(aq)+3PbO2(s)+6H2O(l)→2CrO42-(aq)+3Pb2+(aq)+4H3O+ (aq) a.Which species is the oxidizing agent b.What is the oxidation state of the O in CrO42- c.What is the oxidation state of the Pb in PbO2? d.How many valence electrons are in the CrO42- ion? e. How many moles of electrons, ne, are transferred per mole of this reaction? f. At a certain point the measured free energy is ∆?. Adding more PbO2 will cause the free energy change of the reaction, ∆G, to choose...(Increase, Stay the same, Decrease) g. At a certain point the measured ∆G is –5 kJ/mol. Lowering the pH will cause the free energy change of the reaction, ∆?, to choose...  (become less negative, stay the same, become more negative) h. The reaction is used to set up an electrochemical cell. What is true about the cell if the measured voltage is negative? Choose ? < ?, ? = ?, ? > ?, Need more info I. At 298.2 K, this reaction has an equilibrium constant K = 1.6 × 1013 . What is the…

1. Write a balanced equation for the reaction between sodium carbonate (Na2CO3) andhydrochloric acid (HCl).2. Calculate the theoretical yield (in grams) of the CO2 that should be produced from the massof Na2CO3 used. Use dimensional analysis.3. Use the following equation to calculate the percent yield of the CO2.experimental(actual) %yield x 100theoretical(calculated)=4. Calculate the theoretical yield of NaCl from the amount of Na2CO3 used. Use dimensionalanalysis.5. Use the following equation to calculate the percent yield of the NaCl in your experiment.experimental(actual) %yield x 100theoretical(calculated)

3. Balance the following equation:                Ca3(PO4)2  +    SiO2  -->   CaSiO3  +  P2O5