Sodium bicarbonate is usually found in its white crystalline solid form. Most people know it as the chief ingredient in baking soda, bread soda and cooking soda. Like any chemical compound, it has unique properties and characteristics. These help when you need to test for the compound, since specific tests can utilize reactions exclusive to sodium bicarbonate.

Litmus Test

The fastest way to test for sodium bicarbonate is to find out the substance's pH level by performing a litmus test. If your sample comes in a solid form, simply dissolve it in some distilled water, making sure that the solution is not oversaturated. Next, dip a litmus paper test strip into the solution and wait a few seconds for the color to develop. Check the color on the strip against the reference sheet to determine the approximate pH level of your solution. It is important to use litmus paper that can distinguish between a wide range of pH levels so that your test is more accurate. If your substance is sodium bicarbonate, it should have a pH of around 9.

Flame Test

A more accurate and fun way to test for sodium bicarbonate is to do a flame test. For this you will need a sample of the supposed sodium bicarbonate, a Bunsen burner and a pair of tweezers. Simply take a tiny amount of the chemical and hold it in the flame. Sodium turns yellow over a flame, and carbon turns pinkish-blue, so if you have yellow pinkish-blue colors, odds are you have sodium bicarbonate.

Combination Test

The most accurate test for sodium bicarbonate utilizes litmus paper, lime water and an acid-base reaction. Start out with a small amount of the sample at hand, approximately one gram, and dilute it in about 5ml of distilled water. Be sure that the substance fully dissolves before proceeding. Now take another glass, fill it with lime water, and pour half of the solution into it. Test this second sample for the presence of carbonate by adding about 2ml of hydrochloric acid to it. If it starts to bubble that means it is releasing a gas, hopefully carbon dioxide, which is a tell-tale sign of carbonate. To know for sure if this is the gas, check to see if the lime water turned milky. If it did that means it has reacted with carbon dioxide. If the substance did not at all react with the hydrochloric acid, then it is not a basic, and therefore cannot be sodium bicarbonate. But if there is a confirmed carbonate presence in the substance, test pH again with the litmus paper to see if it is around 9.

Source:

CCSU.edu: Sodium Bicarbonate Test

InfoPlease: Formation of Carbon Dioxide--Sodium Bicarbonate

Encyclopedia.com: Sodium Bicarbonate