Sunday, July 6, 2008

Chemical Equilibrium - Multiple Choice Questions

One Answer only

1. The ion that cannot be precipitated by both HCl and H2S is

a. Pb2+
b. Ag+
c. Cu+
d. Sn2+

(JEE 1982)

Ans: (d)

2. A certain buffer solution contains equal concentration of X- and HX. The Kb for X- is 10-10. The pH of the buffer is:

a. 4
b. 7
c. 10
d. 14
(JEE 1984)

ans: a

3. A certain weak acid has a dissociation constant of 1.0*10-4. The equilibrium constant for its reaction with a strong base is:

a. 1.0*10-4
b. 1.0*10-10
c. 1.0*1010
d. 1.0*1014
(JEE 1984)

Answer: ( c)

4. An example of a reversible reaction is:
(JEE 1985)

5. The conjugate acid of NH2- is:

a. NH3
b. NH4OH
c. NH4+
d. N2H4
(JEE 1985)

Answer: (a)

6. the compound that is not a Lewis acid is:

a. BF3
b. AlCl3
c. BeCl2
d. SnCl4
(JEE 1985)

Answer: (c )

BeCl2 cannot accept a lone pair of electrons.


7. the compound whose 0.1 M solution is basic is:

a. ammonium acetate]
b. ammonium chloride
c. Ammonium sulphate
d. sodium acetate
(JEE 1986)

Answer (d)

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