Order Chemical and Ionic Equilibria Discussion

Order Chemical and Ionic Equilibria Discussion
1. The forward reaction in the system 2NH3(g) N2(g) 3H2(g) has proceeded to 98% under equilibrium. The equilibrium pressure = 10 atm. Temperature = 400qC. Calculate KP
and KC.
2. 3 moles of Iodine and 8 moles of hydrogen are kept at 444qC and at constant volume till equilibrium is established
at which 5.65 moles of H,
(g) are formed H2(g) ,2(g) 2H,(g). If one starts with 5.3 moles of ,
2(g) and 8 moles of
hydrogen, how many moles of H,(g) will be formed at equilibrium (at the same temperature). Give an approximate
estimate.
3. For the equilibrium : N2(g) O2(g)
2NO(g) att 2675qC KP
= 3.5 u 103
. Calculate ‘Gq.
4. When the equilibrium : N2
O4(g) 2NO2(g) is set up at 65qC and at a total (equilibrium) pressure of one atm, the
degree of dissociation = 0.6. If keeping the temperature at the same value, but the pressure is adjusted so that the
volume is reduced to one half of the initial volume, what would be the degree of dissociation?
5. At 2000qC and at 1 atm pressure, degree of dissociation of CO2(g) is only 1.8% :
2CO2(g) 2CO(g) O2(g). Calculate the equilibrium constant.
6. 3.6 g of PCl5
vapour occupies a volume of one litre at an equilibrium pressure of 1 atm at 200qC; PCl5(g) PCl3(g)
Cl2(g). Calculate the degree of dissociation and the equilibrium constant. Molar mass of PCl5
= 208 g mol1
Order Chemical and Ionic Equilibria Discussion
7. Calculate the [H ] in a solution containing a mixture of one mole of acetic acid and one mole of cyano acetic acid in
a litre. Ka
for acetic acid = 1.8 u 105
and Ka
for cyano acetic acid = 3.7 u 103
.
8. Derive an expression for the hydrogen ion concentration in a very dilute solution of acetic acid. Use it to calculate
[H ] in 104
M acetic acid. Ionic product of water Kw = 1014 at 25qC; Ka
for acetic acid = 1.85 u 105
at 25qC.
9. Ka
for acetic acid at 18qC = 1.8 u 105
. Calculate D the degree of dissociation and the hydrogen ion concentration
in (i) 0.25 N acetic acid solution and (ii) a solution which is 0.25 N w.r.t sodium acetate and 0.25 N w.r.t acetic acid
assuming that sodium acetate is completely ionized in solution.
10. At a certain temperature T, solubility of AgBrO3
in water = 8.1 u 103
M. To one litre of the solution 8.5 u 103
mole of AgNO3(s) is added. What is the (new) solubility of AgBrO3
. Assume that both salts are completely ionized in
solution