Question

The formula of soda ash is

• A. $N{a}_{2}C{O}_3.10H_{2}O$
  
  
• B. $N{a}_{2}C{O}_3.H_{2}O$
  
• C. $N{a}_{2}C{O}_3$
  
• D. $N{a}_{2}C{O}_3.2H_{2}O$
  

Answer 1

The correct option is C $N{a}_{2}C{O}_3$


Soda ash is formed when sodium carbonate decahydrate $(i.e.washingsoda$) is heated above $373K$. This cause $N{a}_{2}C{O}_3.10H_{2}O$ to lose all water of crystallisation to form anhydrous sodium carbonate , which is white powder and called as soda ash.

Hence, the Correct answer is Option (D).