The formula of baking soda is :Select the correct answer from the code given below:

1. A

   KHCO₃

   Option (a) claims that KHCO3 is the chemical formula of baking soda. This formula actually represents potassium bicarbonate, which is a different compound altogether. Therefore, this option is incorrect.

2. B

   Na₂CO₃

   Option (b) claims that Na2CO3 is the chemical formula of baking soda. This formula represents sodium carbonate, commonly known as washing soda in its decahydrate form. Hence, this option is incorrect.

3. C

   K₂CO₃

   Option (c) claims that K2CO3 is the chemical formula of baking soda. This formula represents potassium carbonate, historically known as potash. Thus, this option is incorrect.

4. D

   NaHCO₃

   Option (d) claims that NaHCO3 is the chemical formula of baking soda. This compound is chemically known as sodium hydrogen carbonate or sodium bicarbonate, which is widely used in cooking and antacids. As it correctly identifies the formula of baking soda among the given choices, this is the official key.

Summary. Official key is (d) NaHCO3. Baking soda, or sodium bicarbonate, is a white crystalline solid commonly used in baking and as a mild antacid. Students often confuse it with washing soda, which is sodium carbonate decahydrate having the formula Na2CO3 dot 10 H2O. Potassium compounds like KHCO3 and K2CO3 have different chemical properties and commercial names. Understanding the precise chemical formulas of everyday sodium salts is essential for answering such direct chemistry questions accurately in the exam.