0.1 M solution of which one of these substances will be basic?
Sodium borate
Calcium nitrate
NH4Cl
Sodium sulphate
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
The conjugate acid of NH2- is
N2H4
NH4 +
NH2 OH
NH3
Which of the following molecules acts as a Lewis acid ?
(CH3)3B
(CH3)2O
(CH3)3P
(CH3)3N
Aqueous solution of acetic acid contains
CH3COO- and H+
CH3COO-, H3O+ and CH3COOH
CH3COO-, H3O+ and H+
CH3 COOH, CH3COO- and H+H3COOH
The pH value of a 10 m solution of HCl is
less than 0
Equal to 0
Equal to 1
Equal to 2
H2S gas when passed through a solution of cations containing HCl precipitates the cations of second group in qualitative analysis but not those belonging to the fourth group. It is because
Presence of HCl decreases the sulphide ion concentration.
Presence of HCl increases the sulphide ion concentration.
Solubility product of group 2nd sulphides is more than that of group iv sulphides
Sulphides of group iv cations are unstable in HCl
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)
A weak acid HA, has a Ka of 1.00 ×10-5. If 0.100 mole of this acid is dissolved in one litre of water, the percentage of acid dissociated at equilibrium is closest to
99.0%
1.00 %
99.9%
0.100%
The concentration of [H+] and concentration of [OH- ] of a 0.1M aqueous solution of 2% ionised weak monobasic 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
