Among the lanthanides the one obtained by synthetic method is
Lu
Pm
Pr
Gd
The most durable metal plating on iron to protect against corrosion is
Nickel plating
Tin plating
Copper plating
Zinc plating
Which one of the following is an ore of silver?
Argentite
Stibnite
Haematite
Bauxite
When (NH4)2Cr2O7 is heated, the gas evolved is
N2
NO2
O2
N2O
Actinides
are all synthetic elements participate.
Include element 104
have any short lived isotopes
have variable valency
Oxidation state of Fe in Fe3O4 is
3/2
4/5
5/4
8/3
When CuSO4 is electrolysed using platinum electrodes
Copper is liberated at cathode, Sulphur at anode
Copper is liberated at cathode, Oxygen at anode
Sulphur is liberated at cathode, Oxygen at anode
Oxygen is liberated at cathode, Copper at anode
The oxidation state of Cr in K2Cr2O7 is
+5
+3
+6
+7
Which one of the following elements shows maximum number of different oxidation states in its compounds?
Eu
La
Am
The transition elements have a general electronic configuration
ns2np6nd1-10
(n-1)d1-10, ns0-2, np0-6
(n-1)d1-10, ns1-2
nd1-10ns2
