Which of the following molecules acts as a Lewis acid ?
(CH3)3B
(CH3)2O
(CH3)3P
(CH3)3N
The strongest conjugate base is
NO3-
Cl-
SO4 2-
CH3COO-
Which has highest pH ?
CH3COOK
Na2CO3
NH4Cl
NaNO3
What is the [OH-] in the final solution prepared by mixing 20.0 mL of 0.050 M HCl with 30.0 mL of 0.10 M Ba(OH)2?
0.10 MNumber of milliequivalents of HCl =20×0.050×1=1Number of milliequivalents of Ba(OH)2 = 2×30×0.10=6[OH-] of final solution = milliequivalents of Ba(OH)2 - milliequivalents of HCl / Total volume = 6 - 1 / 50=0.1 M
0.40 M
0.0050 M
0.12 M
The solubility product of a sparingly soluble salt AX2 is 3.2 ×10-11. Its solubility ( in mol / L ) is
5.6 ×10-6
3.1 ×10-4
2 ×10-4
4 ×10-4
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 hydride ion H- is strong base than its hydroxide ion OH-. Which 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
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 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 solubility product of CuS ,CdS and HgS are 10-31 , 10-44 , 10-54 , respectively.The solubility of these sulphides are in the order .
CdS > HgS > CuS
HgS > CdS > CuS
CdS > CuS > HgS
CuS > CdS >HgS
