CHEM1084_U8_LAB 8_Prela
Pre Lab Questions
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1. What is the oxidation number of oxygen in HNO3, H2O2, CO2 and Cr2O3?
2. Balance the following reaction equation in an acidic medium:
Fe2+ + MnO XXXXXXXXXXFe3+ + Mn2+
3. Write the equation for the cell reaction and calculate the standard emf of a cell that uses Mg/Mg2+ and Cu/Cu2+ half cell reactions at 25°C under standard state conditions.
Half reactions
Mg2+ (aq) + 2e XXXXXXXXXXMg (s) E° = -2.37 V
Cu2+ (aq) + 2e XXXXXXXXXXCu (s) E° = +0.34 V
4. What is the reduction potential of a cell?
5. Sketch galvanic cell based on the following half-reactions. Label the cathode, anode, electrolyte solutions and the salt
idge. Show the direction of electron flow in external circuit connecting two electrodes and ion migration through the salt
idge (with NaNO3) connecting cell compartments. What is the overall balanced cell reaction?
Reduction half- reaction Ag+ (aq) + e XXXXXXXXXXAg (s)
Oxidation half- reaction XXXXXXXXXXNi (s XXXXXXXXXXNi2+ (aq) + 2e-