Question

NiO2(s) + 2 H2O(l) + Fe(s) → Ni(OH)2(aq) + Fe(OH)2(aq) in basic solution

#1

A.)Examine the following and identify what elements are undergoing oxidation, what are undergoing reduction

B.) Identifty number of electrons exchanged

MS(s) ⇄ M+2(aq) + S-2(aq) Ksp = small number

S-2= weak base

#2Once you identify the nature of S-2 write the appropriate acid or base dissociation reaction and the correct Ka or Kb statement

#3.)

A sample of 0.500 g of sodium carbonate (Na2CO3) and 0.500 g of sodium BiCarbonate are mixed in 300. mL of water. Assuming the carbonate and bicarbonate are the only carbon-based materials in solution driving the buffer, what is the expected pH of the solution.   

Answer 1

1.As you can see in the above reaction NiO₂ is converted to Ni(OH)₂ where its oxidation no changes from +4 to +2 ,so it is undergoing reduction while Fe is converted to Fe(OH)₂ where its oxidation state changes from 0 to +2,so it is undergoing oxidation.

A.MS-->M²⁺+S^2-

As M has +2 charges ,so it has undergone oxidation while S has -2 charges so it has undergone reduction.

B.As we can see both the product species have +2 and -2 charges ,so electrons exchanged =2