Write down the balanced equation for the reaction when:
Carbon dioxide is passed through a suspension of lime stone in water.

The hybridization of carbon atoms in C-C single bond of HC $$ \equiv $$ C - CH = CH₂ is

The degree of dissociation of calcium nitrate in a dilute aqueous solution, containing 7.0 g. of the salt per 100 gm of water at 100^oC is 70%. If the vapour pressure of water at 100^oC is 760 mm, calculate the vapour pressure of the solution.

Zinc granules are added in excess to a 500 ml. of 1.0 M nickel nitrate solution at 25^oC until the equilibrium is reached. If the standard reduction potential of Zn²⁺ | Zn and Ni²⁺ | Ni are -0.75 V and -0.24 V respectively, find out the concentration of Ni²⁺ in solution at equilibrium.