The rust of iron is catalysed by which of the following ?
Fe
O2
Zn
H+
B.
O2
Iron is rusted in presence of oxygen and moisture .
+ H2CO3
At anode
H2CO3 2H+ + CO32-
Fe Fe2+ + 2e-
Fe + O2 + 4H2O Fe2O3 + 8H+
At cathode
H+ + e- H
4H + O2 2H2O
Hence , rusting of iron is catalysed by hydrogen ion (H+)
HF is not preserved in glass bottle because :
it reacts with the visible part of the light
it reacts with the sodium oxide of the glass
it reacts with the aluminium oxide of the glass composition
it reacts with SiO2 of the glass
In a lead storage battery , reaction at cathode is :
Pb + SO42- PbSO4 + 2e-
Pb + PbO2 + 2H2SO4 2PbSO4 + 2H2O
PbSO4 + 2e- Pb + SO42-
PbO2 + 4H+ + SO42- + 2e- PbSO4 + 2H2O
In coagulating the colloidal solution of As2S3 .which has the minimum coagulating value ?
NaCl
KCl
BaCl2
AlCl3