pH is the acidity of the water indicated in the range 0 to 14. Water with pH 1-6 will be acidic, while water with pH 8-14 will be alkaline. Meanwhile, water with a pH of 7 has neutral properties that are safe and suitable for consumption. However, there is also water with acidic or basic properties that are used for the production of goods or laboratory experiments. The difference in the pH of water can occur due to several factors that influence it. What are the factors that affect the pH of the water?

1. CO2 Concentration in Water

The concentration of carbon dioxide (CO2) dissolved in water becomes a factor that affects pH. The reason is carbon dioxide triggers an increase in the concentration of hydrogen ions which makes the pH of the water decrease. That means when carbon dioxide is high, the pH of water automatically becomes acidic. This carbon dioxide can come from the atmosphere and air around polluted water. Apart from pollution, carbon dioxide also comes from the process of plant respiration that occurs at night, where much carbon dioxide is released. This causes the water to have a lower pH than neutral. While during the day, where many plants photosynthesize by releasing oxygen, the pH of the water will rise.

2. Temperature

The temperature at which water is located affects the solubility of carbon dioxide. When water gets a lot of heat intensity from sunlight, the surface temperature will rise. When the surface temperature of the water rises, the solubility of carbon dioxide will decrease so that the pH will rise and the water is alkaline. Meanwhile, when the temperature and temperature decrease, then the surface temperature of the water will come down and automatically the level of carbon dioxide solubility becomes higher. Therefore, when temperatures are cold, the pH of the water will drop and the water will be acidic.

3. Carbonate and Bicarbonate Concentrations

Next, the factors that affect pH are carbonate and bicarbonate ions which are basic. If water has a high enough concentration of carbonate and bicarbonate ions, the pH will change. From what was originally neutral, the water will turn into a base.

If initially acidic, it can turn into neutral after receiving additional carbonate ions and bicarbonate ions. Changes in water into a base due to carbonate and bicarbonate ions often occur in water flowing out of the mouth of the cave by passing carbonate rocks that contain calcium.

4. Organic Material Decomposition Process

Decomposition is the process of decay that occurs in organic matter and living things that are in the water. Because organic matter and living things contain the element carbon (C), so when the decomposition process occurs, there will be a lot of carbon released into the water. However, because organic compounds tend to be unstable and easily oxidized, what enters the water is carbon dioxide and water itself.

Therefore, when there is carbon dioxide entering the water, it is certain that the pH level will change. Water that was originally neutral can become acidic because the dissolved inorganic carbon content can increase hydrogen ions so that the pH will decrease. Therefore, when working in a laboratory or industrial production process, it is better to keep water away from organic materials that can change the initial pH.

It can be concluded that the factors that affect the pH of the water are all due to the influx of carbon dioxide which causes the pH to change. However, it does not rule out the possibility that temperature also affects the pH of water. To be sure, you can always check the acidity with Mettler Toledo pH meters from Hyprowira.