The reaction quotient 'Q' is useful in predicting the direction of the reaction. Which of the following is incorrect?
If Qc < Kc, the forward reaction is favoured
If Qc > Kc, the forward reaction is favoured
If Qc >Kc, the forward reaction is favoured and Qc =Kc, no reaction occur.
None of these
pH of 1M NH3 aqueous solution is (Kb = 1.8 × 10-5)
11.13
12.5
13.42
11.55
A.
11.13
Kb = 1.8 × 10-5 [NH3] = 0.1 M
NH3 + H2O NH + OH-
Let concentration of [NH] = [OH-] = x
x2 = 1.8 × 10-6
x = 1.35 × 10-3
[OH-] = 1.35 × 10-3
pOH = -log (1.35 × 10-3)
= 2.87
pH = 14 - pOH
= 14 - 2.87 = 11.13
Equivalent weight of an acid :
depends on the reaction involved
depends upon the number of oxygen atoms present
is always constant
None of the above
Two moles of PCl5 were heated in a closed vessel of 2 L. At equilibrium, 40% of PCl5 is dissociated into PCl3 and Cl3. The value of equilibrium constant is :
0.53
0.267
2.63
5.3
The solubility product of Barium sulphate is 1.5 × 10-9 at 18°C. Its solubility in water at 18°C is :
1.5 × 10-9
1.5 × 10-5
3.9 × 10-9
3.9 × 10-5
Which one of the following is called amphoteric solvent ?
Ammonium hydroxide
Chloroform
Benzene
Water
100 mL of 0.04 N HCl aqueous solution is mixed with 100 mL of 0.02 N NaOH solution. The pH of the resulting solution is
1.0
1.7
2.0
2.3
If a system is at equilibrium, the rate of forward to the reverse reaction is :
less
equal
high
at equilibrium
The equilibrium constant for the reaction N2(g) + O2(g) 2NO(g) is 4×10-4 at 200K. In presence of a catalyst the equilibrium is attained ten times faster. Therefore the equilibrium constant in presence of catalyst 2000 K is
4×10-3
4×10-2
40×10-4
4×10-4