Question

The raw materials in Solvay Process are:
A.$NaCl,Ca{(OH)_2}$
B.$NaCl,N{H_4}OH$
C.$NaCl,CaC{O_3},N{H_3}$
D.$NaCl,C{O_2}$

Answer 1

Solvay Process is used for the preparation of sodium carbonate or in simpler terms washing soda . The raw materials of the process are – sodium chloride, calcium carbonate, ammonia.Washing soda is used for many purposes that includes laundry, making glasses .

Complete Step by step answer: It is used for the preparation of washing soda .
In this process, the low solubility of sodium hydrogencarbonate is an important factor .
Here are the steps of the reaction :
First of all calcium carbonate is heated and decomposed into calcium oxide and carbon dioxide.
$CaC{O_3} \to CaO + C{O_2}$
The carbon dioxide extracted from here plays an important role in further process.
Step 1 : Formation of ammonium carbonate.
Ammonia is reacted with carbon dioxide to form ammonium carbonate.
$2N{H_3} + {H_2}O + C{O_2} \to {(N{H_4})_2}C{O_3}$

Step 2 : Excess of carbon dioxide is formed to convert ammonium carbonate into ammonium hydrogencarbonate .
${(N{H_4})_2}C{O_3} + {H_2}O + C{O_2} \to 2N{H_4}HC{O_3}$

Step 3 : Now the ammonium bicarbonate is reacted with sodium chloride . Sodium from sodium chloride replaces ammonia from ammonium bicarbonate and sodium bicarbonate is formed .
$N{H_4}HC{O_3} + NaCl \to N{H_4}Cl + NaHC{O_3}$
Sodium hydrogencarbonate is obtained from here. It is then further heated to give sodium carbonate i.e. washing soda.
$2NaHC{O_3}\xrightarrow{\Delta }N{a_2}C{O_3} + C{O_2} + {H_2}O$
This is what the Solvay process is and this is how washing soda is prepared.
Out of the given options, we can clearly identify what the raw materials are - $CaC{O_3},NaCl,N{H_3},{H_2}O$

Hence, the correct option is C.

Note: We need to keep in mind one important factor here that is that ammonium hydrogen carbonate reacts with sodium chloride to precipitate out sodium hydrogen carbonate. This implies that sodium bicarbonate is not much soluble in brine solution.