Please choose the correct answer to the question: Sodium bicarbonate (NaHCO_{3}) is commonly known as baking soda. Sodium bicarbonate is a white solid that can dissolve in water. Under the proper conditions, sodium bicarbonate can release carbon dioxide (CO_{2}) gas. Which of the following is not a physical property of sodium bicarbonate?

Answer1: It is white. Answer2: It is a solid. Answer3: It can dissolve in water. Answer4: It releases carbon dioxide.

Answer format: answer1/answer2/answer3/answer4
Answer: answer4