Which of the following reactions are disproportionation reactions?
(a) Cu+ → Cu2+ + Cu
(b) 3Mn\(\rm O^-_4\) + 4H+ → 2Mn\(\rm O^-_4\) + MnO2 + 2H2O
(c) 2KMnO4 → K2MnO4 + MnO2 + O2
(d) 2Mn\(\rm O^-_4\) + 3Mn2+ + 2H2O → 5MnO2 + 4H+
1
a, b
2
a, b, c
3
a, c, d
4
a, d