How to identify sodium carbonate and sodium bicarbonate?

Sodium carbonate and sodium bicarbonate are actually two substances, so they should not be confused. This is mainly because their shapes and colors are similar, so it is difficult to distinguish them. If you want to effectively identify them, you can use observation or heating methods. Generally, the gas that turns clear lime water turbid after heating is sodium bicarbonate.

Method 1: Observation

Both are white in solid state. The powdery substance is sodium carbonate, and the crystalline substance is sodium bicarbonate.

Method 2: Heating method

1. The gas that can make clear lime water turbid after heating is sodium bicarbonate, and the opposite is true for sodium carbonate.

2. Weigh its mass before and after heating. If the mass decreases, it is sodium bicarbonate, otherwise it is sodium carbonate.

Method 3: Gas method

Take appropriate amounts of the two solutions to be tested, add a small amount of hydrochloric acid, and then a sodium bicarbonate solution that can immediately produce bubbles. The solution that produces bubbles more slowly is the sodium carbonate solution.

Method 4: Precipitation method

Take appropriate amounts of the two solutions to be tested, add appropriate amounts of barium chloride solution or calcium chloride solution, and the one that can produce precipitation is sodium carbonate solution.

Method 5: pH measurement

When two dilute solutions of the same concentration are measured with a pH meter, the sodium carbonate solution has a higher pH.