Question

Match List - I with List - II : 

Choose the correct answer from the options given below : 
 

• (a) - (iv), (b) - (iii), (c) - (i), (d) - (ii)
• (a) - (v), (b) - (i), (c) - (ii), (d) - (iv)
• (a) - (v), (b) - (ii), (c) - (iv), (d) - (i)
• (a) - (v), (b) - (iii), (c) - (ii), (d) - (i)

Hint:

Alkali metals have very specific industrial uses. Remember these key applications: Li in alloys and batteries, Na as a coolant and in organic synthesis, K in fertilizers and as a CO$_2$ absorbent, and Cs in photoelectric cells and atomic clocks.

Answer 1

The Correct Option is D

Let's match each alkali metal from List-I with its specific use from List-II.
(a) Lithium (Li): Lithium is used to make alloys. For example, 'white metal', an alloy of lithium with lead, is used to make bearings for motor engines. So, (a) matches with (v).
(b) Sodium (Na): Liquid sodium metal is an excellent heat transfer medium and is used as a coolant in fast breeder nuclear reactors. So, (b) matches with (iii).
(c) Potassium (K): Potassium hydroxide (KOH) is a strong base and an excellent absorbent for carbon dioxide (CO$_2$). Also, potassium superoxide (KO$_2$) is used in breathing apparatus as it absorbs CO$_2$ and releases O$_2$. So, (c) matches with (ii).
(d) Caesium (Cs): Caesium has a very low ionization enthalpy, meaning it can lose an electron easily when exposed to light. This property makes it extremely useful in photoelectric cells. So, (d) matches with (i).
The correct matching is: (a) $\rightarrow$ (v), (b) $\rightarrow$ (iii), (c) $\rightarrow$ (ii), (d) $\rightarrow$ (i).
This corresponds to option (D).