Question

A hydrogen carbonate which exists in solid state

Answer 1

NahCO3 ( sodium bicarbonte) is the hydrogen carbonate which rxists in solid state.

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Answer 2

ANSWER
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Hydrogen Carbonate is also known as Bicarbonate (HCO3) -1

One Bicarbonate which exist in solid state is Sodium Bicarbonate (NaHCO3)

About NaHCO3 :
Sodium bicarbonate, commonly known as baking soda, is a chemical compound with the formula NaHCO₃. It is a salt composed of sodium ions and bicarbonate ions. Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. 

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