Cr O 14H 6e 2Cr 7H O; -> E 1.33V. At [Cr O ]l 4.5 millimoles, [Cr3+] = 15 millimoles, E is 1.067 V. The pH of the solution is nearly equal to [KCET 2016]

2 3 2 7 2 Cr O 14H 6e 2Cr 7H O; -> 2 7 3 2 14 2 2 7 Cr H O 0.059 E E log n Cr O H 3 14 3 6 14 3 0.059 1.067 1.33 log 6 15 10 4.5 10 H 0.059 225 10 log 0.263 6 4.5 10 H x x x x x 3 14 3 14 0.263 6 50 10 log 0.059 H log(50 10 ) log(H ) 26.74 x x >> x 1.3010 14log[H ] 26.74 14log H 26.74 1.30101 or 14pH 28.041 pH log H 28.041 pH 2 14 29. Standard electrode potential data are useful for understanding