For the following equilibrium, N2O4 2NO2 in the gaseous phase, NO2 is 50% of the total volume when equilibrium is set up. Hence, per cent of dissociation of N2O4 is
50%
25%
66.66%
33.33%
1 mL of 0.01 N HCl is added to 999 mL solution of 0.1 N Na2SO4. The pH of the resulting solution will
2
7
5
1
The equilibrium constants for the reaction,
Br2 2Br → 1
at 500 K and 700 K are 1 × 10-10 and 1 × 10-5 respectively. The reaction is
endothermic
exothermic
fast
slow
A.
endothermic
Chemical equilibrium constant for the reaction is
Br2 2Br is
Kc =
Kc at 500 K is 1 × 10-10. On increasing temperature (700 K), the value of Kc is also increased, i.e. concentration of product is increased. The increase of temperature will favour the forward reaction. Thus, the formward reaction is endothermic.
A chemist wishes to prepare a buffer solution of pH = 2.90 that efficiently resists a change in pH yet contains only small concentration of buffering agents which one of the following weak acid along with its salt would be best to use
m-chlorobenzoic acid (pKa = 3.98)
Acetoacetic acid (pKa = 3.58)
2 5-dihydrobenzoic acid (pKa = 2.97)
p-chlorocmanic acid (pKa = 4.41)
NaOH is a strong base. What will the be pH of 5.0 × 10-2 M NaOH solution? (log 2 = 0.3)
14.00
13.70
13.00
12.70
The equilibrium constants of the reactions
and are K1 respectively. The relationship between K1 and K2 will be
K2
K2 = √K1
K1= K2
The value of Kc for the dissociation reaction, H2 (g) 2H (g) is 1.2 × 10-42
This equilibrium mixture contains mainly
H2 (g)
H (g) atom
1.1 M mixture of H2 and H
1.2 M mixture of H2 and H