A chemist wishes to prepare a buffer solution of pH = 2.90 that efficiently resists a change in pH yet contains only small concentration of buffering agents which one of the following weak acid along with its salt would be best to use
m-chlorobenzoic acid (pKa = 3.98)
Acetoacetic acid (pKa = 3.58)
2 5-dihydrobenzoic acid (pKa = 2.97)
p-chlorocmanic acid (pKa = 4.41)
NaOH is a strong base. What will the be pH of 5.0 × 10-2 M NaOH solution? (log 2 = 0.3)
14.00
13.70
13.00
12.70
The equilibrium constants of the reactions
and are K1 respectively. The relationship between K1 and K2 will be
K2
K2 = √K1
K1= K2
The value of Kc for the dissociation reaction, H2 (g) 2H (g) is 1.2 × 10-42
This equilibrium mixture contains mainly
H2 (g)
H (g) atom
1.1 M mixture of H2 and H
1.2 M mixture of H2 and H
Among the following, the equilibrium which is not affected by an increase in pressure is
C(s) + H2O (g) CO(g) + H2(g)
3Fe(s) + 4H2O (g) Fe3O4 (s) + 4H2(g)
2SO3(g) 2SO2(g) + O2 (g)
H2 (g) + I2(s) 2Hi(g)
Ksp of CaSO4 is 4 × 10-12. CaSO4 is precipitated on mixing equal volumes of the following solutions.
3 × 10-10 M CaCl2 and 3 × 10-6 M (NH4)2SO4
4 × 10-6 M CaCl2 and 3 × 10-6 M (NH4)2SO4
6 × 10-6 M CaCl2 and 3 × 10-16 M (NH4)2SO4
In all the above cases
What is pH of 2 x 10-8 molar HCl solution? Here, log 2 = 0.301 and log 3 = 0.477.
6.92
9.5
5.4
7.7
Which one of the following species acts as both Bronsted acid and base?
H2PO
HPO
HPO
All of these
The reaction, SO2 + O2 → 2SO2 + Heat.
The equilibrium reaction proceeds in forward direction by
addition of O2
removal of O2
addition of inert gas
cannot proceed
A.
addition of O2
According to Le-Chateher's principle, equilibrium shift towards forward direction by addition of reactant.
Which is soluble in NaNO3 and dil. HCl mixture and forming salt?
(CH3)3CNH2
(CH3)2CHNH2
(CH3)2NH
(CH3)3N