Question

List I	List II
A. Van Arkel method	I. Purification of titanium
B. Solvay Process	II. Manufacture of $N{a}_{2}C{O}_3$
C. Cupellation	III. Purification of copper
D. Poling	IV. Refining of silver

Match list I with list II and select the correct answer using the codes given below the lists:

• A. A - I, B - II, C - IV, D - III
• B. A - II, B - I, C - III, D - IV
• C. A - IV, B - II, C - I, D - III
• D. A - III, B - I, C - II, D - IV

Answer 1

Answer: (A)

A - I, B - II, C - IV, D - III

A. Van-Arkel method: This method is used for ultrapure metal like Ti, Zr etc. The metal is converted into its volatile stable compound such as $Ti{I}_4$, leaving behind impurities. The stable volatile compound thus formed is decomposed to get pure metal.

$\frac{Ti}{\left(impure\right)}+2I_2\stackrel{500k}{\to }Ti{I}_4\stackrel{1675K}{\to }Ti+\frac{2I_2}{\left(pure\right)}$

B. Solvay process: The Solvay Process, used in the manufacture of $N{a}_{2}C{O}_3$ is a continuous process using limestone ($CaC{O}_3$) to produce carbon dioxide ($C{O}_2$) which reacts with ammonia ($N{H}_3$) dissolved in brine (concentrated $NaCl$(aq)) to produce sodium carbonate.

C. Cupellation: Pb present in Ag is removed by this method. The impure metal is heated in a cupel or oval-shaped crucible made of bone ash or cement and the blast of air is passed over the molten mass. The impurities get oxidized and removed with the blast of air.

D. Poling: The molten impure metal (Cu) containing oxides as impurities are stirred with green poles of wood which releases hydrocarbon gases. The hydrocarbon gases reduce oxide to metal.

A - I, B - II, C - IV, D - III

Option A is correct.