Li1+yCoO2 is an anode for lithium batteries. Cobalt (58.933 amu) is present as a mixture of Co(III) and Co(II). Most preparations also contain inert lithium salts and moisture. To find the stoichiometry, Co was measured by atomic absorption and its average oxidation state was measured by potentiometric titration. For the titration, 25.00 mg of solid were dissolved under N2 in 5.00 ml containing 0.1000 M Fe2+ in 6 M H3PO4 plus 6 M H3PO4 to give a clear pink solution: Co3+ + Fe2+ - Co2+ + Fe3+ . Unreacted Fe2+ required 3.228 ml of 0.01593 M K2Cr2O7 for complete titration, where the chromium...

Question

Li1+yCoO2 is an anode for lithium batteries. Cobalt (58.933 amu) is present as a mixture of Co(III) and Co(II). Most preparations also contain inert lithium salts and moisture. To find the stoichiometry, Co was measured by atomic absorption and its average oxidation state was measured by potentiometric titration. For the titration, 25.00 mg of solid were dissolved under N2 in 5.00 ml containing 0.1000 M Fe2+ in 6 M H3PO4 plus 6 M H3PO4 to give a clear pink solution: Co3+ + Fe2+ -> Co2+ + Fe3+ . Unreacted Fe2+ required 3.228 ml of 0.01593 M K2Cr2O7 for complete titration, where the chromium...

pamelanicole · Answer

...is reduced to Cr3+.if atomic absorption found 56.4188 wt% Co in the solid, determine y in the formula Li1+yCoO2.