Multiple Choice QuestionsOn 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
A.
the basic strength of hydrides increases
As we move down the group, the size of the central atom goes on increasing and its electronegativity goes on decreasing. As a result the force of repulsion between the adjacent bond pairs is maximumin NH3 and minimum in SbH3. Consequently the bond angle is maximumin NH3 and minimum in SbH3.
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)
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
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