When MnO2 is fused with KOH, a colouredcompound is formed. The product and its colour is:
K2MnO4 , purple colour
Mn2O3 , brown
Mn2O4 , black
KaMnO4 , purple
In [NiCl4]2-, the number of unpaired electrons, are
4
2
3
5
B.
2
In [NiCl4]2- the oxidation number of Ni is +2.
Electronic configuration of Ni (atomic no = 28)
Ni = [Ar] 3d84s2
Ni+2 = [Ar] 3d8
or [Ar]
It is evident that in [NiCl4]2- the number of unpaired electrons are two.
H2C2O4 + KMnO4 in acidic medium reacts to have change in oxidation number of Mn from
7 to 5
2 to 7
5 to 7
7 to 2
For which of the following elements it is difficult to disproportionate in +3 oxidation state ?
N
As
Sb
Bi
Substances that are oxidised and reduced in the following reaction are respectively
N2H4 (l) + 2H2O2 (l) N2 (g) + 4H2O (l)
N2H4, H2O
N2H4, H2O2
N2, H2O2
H2O, N2