Equal volumes of three acid solutions of pH 3.4 and 5 are mixed in a vessel. What will be the H+ ion concentration in the mixture?
1.11 x 10-4 M
3.7 x 10-4 M
3.7 x 10-3 M
3.7 x 10-3 M
The angular shape of ozone molecule (O3) consists of
1 sigma and 2 pi bonds
2 sigma and 2 pi bonds
1 sigma and 1 pi bonds
1 sigma and 1 pi bonds
Which of the following are not state functions?
I) q + W
II) q
III) W
IV) H-TS
(I) and (IV)
(II) (III) and (IV)
(I), (II) and (III)
(I), (II) and (III)
The correct order of decreasing second ionisation enthalpy of Ti (22), V (23), Cr(24) and Mn (25) is
Cr > Mn> V > Ti
V > Mn > Cr >Ti
Mn > Cr> Ti >V
Mn > Cr> Ti >V
A.
Cr > Mn> V > Ti
The amount of energy required to remove an electron from unipositive ions is called the second IP which generally increases in a period from left to right.
The second ionisation energies of the first transition series increase almost regularly with an increase in atomic number. However, the value for Cr is sufficiently higher than those of its neighbour ie, (Mn). This is due to the stable configuration of Cr3+ (3d5 exactly half filled.)
[Note: The half-filled and completely filled configuration are more stable.]
If a gas expands at constant temperature, it indicates that
the kinetic energy of molecules decrease
the pressure of the gas increases
the kinetic energy of molecules remains the same
the kinetic energy of molecules remains the same
For the gas phase, reaction,
PCl5 (g) ⇌ PCl3 (g) Cl2 (g)
Which of the following conditions are correct?
Δ H = 0 and ΔS > 0
ΔH >0 and ΔS > 0
Δ H < 0 and ΔS < 0
Δ H < 0 and ΔS < 0
Number of moles of MnO4- required to oxidies one mole of ferrous oxalate completely in acidic medium will be
0.6 mole
0.4 mole
7.5 mole
7.5 mole
If the concentration of OH- ions in the reaction Fe(OH)3 (s) ⇌ Fe3+ (aq) + 3OH-(aq) is decreased by 1/4 times, then equilibrium concentration of Fe3+ will increase by
8 times
16 times
64 times
64 times
The sequence of ionic mobility in aqueous solution is
K+ > Na+ > Rb+ > Cs+
Cs+ > Rb+ > K+ >Na+
Rb+ > K+> Cs+ > Na+
Rb+ > K+> Cs+ > Na+