The solubility product of CuS ,CdS and HgS are 10-31 , 10-44 , 10-54 , respectively.The solubility of these sulphides are in the order of
CdS > HgS > CuS
HgS > CdS > CuS
CdS > CuS > HgS
CuS > CdS >HgS
A Physician wishes to prepare a buffer solution at pH =3.58 that efficiently resist changes in pH yet contains only small concentration of the buffering agents. Which one of the following weak acid together with its sodium salt would be best to use ?
m-chlorobenzoic acid (pKa=3.98)
P-Chlorocinnamic acid(pKa = 4.41)
2,5 -dihydroxy benzoic acid (pKa=2.97)
Acetoacetic acid(pKa=3.58)
0.1 mole of CH3NH2 (Kb = 5 × 10-4 ) is mixed with 0.08 mole of HCl and diluted to one litre. What will be the H+ concentration in the solution?
8 × 10-2 M
8 × 10-11 M
1.6 × 10-11 M
8 × 10-5 M
The pKα of a weak acid, HA is 4.80. The Kb of a weak base BOH is 4.78. The pH of an aqueous solution of the corresponding salt BA , will be
7.01
9.22
9.58
4.79
At constant temperature, the equilibrium constant (K p) for the decomposition reaction,
where , p= pressure, x= extent of decomposition. Which one of the following statement is true?
K p increases with increase of p
K p increases with increase of x
K p increases with decrease of x
Kp remains constant with change in p and x
The values of Kp1 and Kp2 for the reactions and are in ratio of 9:1.If degree of dissociation of x and A be equal, then total pressure at equilibrium (i) and (ii) are in the ratio of
3:1
1:9
36:1
1:1
The concentration of [H+] and concentration of [OH- ] of a 0.1M aqueous solution of 2% ionized weak mono basic acid is [ionic product of water = 1×10-14 ]
0.02×10-3 M and 5×10-11 M
1×10-3 M and 3×10-11 M
2×10-3 M and 5×10-12 M
3×10-2 M and 4×10-13 M
The pH value of blood does not change appreciably by a small addition of an acid or base, because the blood -
is a body fluid
can be easily coagulated
contains iron as a part of the molecule
contains serum protein that acts as buffer
The pH of 0.1 M solution of a weak acid is 3. What is the value of the ionization constant for the acid?
0.1
10-3
10-5
10-7
The solubility of a saturated solution of calcium fluoride is 2×10-4 mol / L . Its solubility product is,
12×10-2
14×10-4
22×10-11
32×10-12
