Which of the following pairs of a chemical reaction is certain to result in a spontaneous reaction?
Exothermic and decreasing disorder
Endothermic and increasing disorder
Exothermic and increasing disorder
Endothermic and decreasing disorder
The number of moles of KMnO4 reduced by one mole of KI in alkaline medium is
one-fifth
five
one
two
D.
two
In alkaline solution, KMnO4 is reduced to MnO2 (colourless).
Hence, two moles of KMnO4 are reduced by one mole of KI.
The mass of carbon anode consumed (giving only carbondioxide) in the production of 270 kg of aluminium metal from bauxite by the Hall process is (Atomic mass Al= 27)
180 kg
270 kg
540 kg
90 kg
A nuclide of an alkaline earth metal undergoes radioactive decay by emission of three -particles in succession. The group of the periodic table to which the resulting daughter element would belong to
Group 14
Group 16
Group 4
Group 6
A reaction occurs spontaneously if
TS < H and both H and S are +ve
TS > H and both H and S are +ve
TS = H and both H and S are +ve
TS > H and H is +ve and S is - ve
Equilibrium constants K1 and K2 for the following equilibria
NO (g) + NO2(g) and
2NO2(g) 2NO (g) + O2(g)
are related as
The absolute enthalpy of neutralisation of the reaction
MgO(s) + 2HCl(aq) MgCl2(aq) + H2O(l)
will be
less than - 57.33 kJ mol-1
- 57.33 kJ mol-1
greater than-- 57.33 kJ mol-1
57.33 kJ mol-1
The correct sequence of increasing covalent character is represented by
LiCl < NaCl < BeCl2
BeCl2 < NaCl < LiCl
NaCl < LiCl < BeCl2
BeCl2 < LiCl < NaCl