How many atoms constitute one unit cell of a face-centered cubic crystal? 

Name the method used for the refining of Nickel metal?

What is the covalency of nitrogen in N₂O₅? 

Arrange the following in increasing order of their basic strength in aqueous solution: 

 CH₃NH₂, (CH₃)₃N, (CH₃)₂NH

5.

18 g of glucose, C₆H₁₂O₆ (Molar Mass = 180 g mol^-1) is dissolved in 1 kg of water in a saucepan. At what temperature will this solution boil? 

 (K_b for water = 0.52 K kg mol^-1, boiling point of pure water = 373.15 K)

The conductivity of 0.20 M solution of KCl at 298 K is 0.025 S cm^-1. Calculate its molar conductivity?

Write the dispersed phase and dispersion medium of the following colloidal systems: 

 (i) Smoke (ii) Milk

What are lyophilic and lyophobic colloids? Which of these sols can be easily coagulated on the addition of small amounts of electrolytes?

Write the differences between physisorption and chemisorption with respect to the following:

(i) Specificity

(ii) Temperature dependence

(iii) Reversibility and

(iv) Enthalpy change

Which solution is used for the leaching of silver metal in the presence of air in the metallurgy of silver?