On reduction of KMnO4, by oxalic acid in acidic medium, the oxidation number of Mn changes. What is the magnitude of this change?
From 7 to 2
From 6 to 2
From 5 to 2
From 7 to 4
Zinc and mercury do not show variable valency like d-block elements because
they are soft
their d- shells are complete
they have only two electron in the outer most sub shell
Their d- shell are completed
A deep brown gas is formed by mixing two colourless gases which are
NO2 and O2
N2O and NO
NO and O2
NH3 and HCl
In the nitrogen family the H-M-H bond angle in the hydrides (MH3 ) gradually becomes closer to 90° on going from N to Sb. This shows that
the basic strength of hydrides increases
the bond energies of M-H bonds increases
almost pure p-orbitals are used for M-H bonding
the bond pairs of electrons come nearer to the central atom
The pair of coordination compounds [Co(NH3)5Br]SO4 and [Co(NH3)5SO4]Br is an example for
geometrical isomerism
coordination isomerism
structural isomerism
ionisation isomerism
The correct nomenclature Fe4[Fe(CN)6]3
ferroso ferric cyanide
ferric- ferrous hexacyanate
iron(III) hexacyanoferrate(II)
hexa cyanoferrate(III-II)
C.
iron(III) hexacyanoferrate(II)
Fe4[Fe(CN)6]3 - iron(III) hexacyanoferrate(II)
Which one of the following will give a white precipitate with AgNO3 in aqueous medium?
[Co(NH3)2Cl] (NO2)2
[Pt(NH3)2Cl2]
[Pt(en) Cl2]
[Pt(NH3)4]Cl2
Which one of the following sulphide is yellow?
Zinc sulphide
Cadmium sulphide
Nickel sulphide
Lead sulphide