Solve the riddle using the given clues:
Sheela got a chocolate by identifying a correct unknown substance using the hints below. What is the name of the substance she answered, find this using the below puzzle.
“X is a chemical sample. It is useful in fire extinguishers.
And it is useful in making cakes. It can be neutralise excess acids in your stomach. Identify the X.
“X is a chemical sample. It is useful in fire extinguishers.
And it is useful in making cakes. It can be neutralise excess acids in your stomach. Identify the X.

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