Calculate the pOH of a solution at 250C that contains 1.0×10-6 M of hydronium ions .
7.00
4.00
9.00
1.00
The pH value of 10 m solution of HCl is_____________
less than 0
Equal to 0
Equal to 1
Equal to 2
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%
Aqueous solution of acetic acid contains___________
CH3COO- and H+
CH3COO-, H3O+ and CH3COOH
CH3COO-, H3O+ and H+
CH3 COOH, CH3COO- and H+H3COOH
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
Which one of the following substance will have 0.1M solution of basic?
Sodium borate
Calcium nitrate
NH4Cl
Sodium sulphate
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)
The hydride ion H- is strong base than its hydroxide ion OH-. Which one of the following reactions will occur if sodium hydride (NaH) is dissolved in Water ?
2H-(aq) + H2O(l)→H2O+H2 +2e-
H-(aq) + H2O(l)→OH-+H2
H - + H2O(l) → no reaction
None of the above
The compound whose aqueous solution has the highest pH is______________
NaCl
NaHCO3
Na2CO3
NH4 Cl
Which of the following molecules acts as a Lewis acid ?
(CH3)3B
(CH3)2O
(CH3)3P
(CH3)3N
