The most durable metal plating on iron to protect against corrosion is
Nickel plating
Tin plating
Copper plating
Zinc plating
K2Cr2O7 on heating with aqueous NaOH gives
CrO42-
Cr(OH)3
Cr2O72-
Cr(OH)2
Oxidation state of Fe in Fe3O4 is
3/2
4/5
5/4
8/3
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
Which one of the following elements shows maximum number of different oxidation states in its compounds?
Eu
La
Gd
Am
Cuprous compounds such as CuCI, CuCN and CuSCN are the only salts stable in H2O due to
high hydration energy of Cu+ ions
their inherent tendency not to disproportionate
diamagnetic nature
insolubility in water
The common oxidation states of Ti are
+2,+3
+3,+4
+1,+2
+2, +3, +4
Stainless steel contains iron and
Cr + Ni
Cr + Zn
Zn + pb
Fe + Cr + Ni
Among the lanthanides the one obtained by synthetic method is
Lu
Pm
Pr
The oxidation state of Cr in K2Cr2O7 is
+5
+3
+6
+7
