- 1). Pour 1 cup of water into the glass container. Adding the water first will ensure that the soda ash fully dissolves into solution and will avoid any residue sticking to the bottom of the container.
- 2). Add 1 tbsp. of soda ash to the water and stir to dissolve it, creating your sodium carbonate solution.
- 3). Dip and hold the bottom half of the pH indicator strip in the solution.
- 4). Pour vinegar into the solution slowly, watching for the color change on the indicator showing that the pH is between 8 and 9. The highest concentration of sodium bicarbonate is achieved at a pH of 8.4, but between a pH of 8 and 9 the solution is primarily sodium bicarbonate and can be used to clean.
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