Manganese salt + PbO2 + conc. HNO3 → the solution acquires purple colour. The colour is due to
Mn(NO3)2
Pb(NO3)2
HMnO4
MnO
Acidified solution of chromic acid on treatment with H2O2 yields
CrO3 + H2O + O2
Cr2O3 + H2O + O2
CrO5 + H2O
H2Cr2O7 + H2O + O2
German silver contains which following metals?
Cu, Zn
Fe, Zn
Zn, Fe, Ni
Cu, Zn, Ni
D.
Cu, Zn, Ni
German silver (nickel silver) is an alloy of copper, zinc and nickel often in the proportions 5 2 2.It is used in cheap jewellery and cutlery.
What is the change in the oxidation state of Mn in the reaction of MnO with H2O4 in acidic medium?
7 ➔4
6➔4
7➔2
6➔2
The following reaction occurs in acidic medium KMnO4 + 8H+ + 5e- → K+ + Mn2+ + 4H2O. What is the equivalent weight of KMnO4 ?
(Molecular weight of KMnO4 = 158)
79.0
31.6
158.0
39.5
The maximum number of possible oxidation states of actinoides are shown by-
Neptunium (Np) and plutonium (Pu)
Nobelium (No) and lawrencium (Lr)
Berkelium (Bk) and californium (Cf)
Actinium (Ac) and throrium (Th)
The maximum possible denticities of a ligand given below towards a common transition and inner-transition metal ion, respectively, are :
8 and 8
6 and 8
8 and 6
6 and 6