XI Chemistry Solved Numerical Question - Chapter No.7 Chemical Equilibrium

1. At 444°C reaction of hydrogen and iodine is performed in a sealed 1 dm3 steel vessel. If equilibrium mixture contains 1 mole of H2, 1 mole of I2 and 7 moles of HI. Calculate (a) Equilibrium constant (Kc) (b) Initial concentration of H2 and I2 2. Lead fluoride (PbF2) is a high melting white solid used in glass coating to reflect IR rays. Its solubility in water at 25°C is 0.58g/dm3. Calculate its Ksp. (At. mass of Pb = 207 and F = 19) 3. A solution of CaCO3 is prepared by mixing 200cm3 of 2.4 x 10-4M Ca(NO3)2 and 300cm3 of 4.5 x 10-2M K2CO3. Will CaCO3 precipitate upon cooling to 25°C if Ksp of CaCO3 at 25°C is 3.8 x 10-9. 4. Hydrogen iodide is a colourless gas prepared by reacting H2 and I2. In an equilibrium study of above reaction, 1.2 mole of H2 and 1.2 moles of 12 were injected in an evacuated 1000cm3 sealed flask and start the reaction to occur at 440°C until the equilibrium is formed. If Kc for this reaction is 49, calculate the equilibrium concentration of H2, 12 and HI.