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The pH of deionized water tends to be lower than normal water because the dissolved salts (ions) in the normal water can somewhat neutralize or "buffer" the carbon dioxide (CO2) that is also dissolved in the water. There is always some CO2 dissolved in water that comes from the air, and this CO2 exists in the water as H2CO3 (carbonic acid), as well as the bicarbonate ion (HCO3-) and carbonate ion (CO3 --) in solution. When there are no other ions in the water, the HCO3 has a stronger effect on the pH, because without other ions to buffer the acid, the water becomes very sensitive to small amounts of CO2 and the result is that the pH is lower. To make deionized water, the water is passed through ion-exchange resins that remove ions like Na+ and Ca++ and replace them with H+, and remove ions like Cl- and replace them with OH-. This process can also affect the pH but the overall affect is still from the dissolved CO2 that will still be present, or will re-dissolve in the water after deionization from contact with air. Deionization does NOT sterilize the water unless some sterilization method is also used. Distilled water is somewhat like deionized water except that the water is boiled to make water vapor and then condensed back to liquid water, leaving the dissolved salts (ions) behind. This can have some sterilization effect as well. Sterilized water is typically heated and cooled, killing organisms, but this does not remove the salts or ions. Reverse osmosis is a filtration process that can remove ions AND sterilize the water to a large extent. There are home units available that can be mounted under the sink but they are pretty expensive. From a chemist working in the water treatment industry
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What is the pH level for deer park bottled water?
Ultrapure water has the pH=7; bottled water is not pure, so the pH is variable depending to the type of water.
What is the pH level of Kroger purifed water?
Purified water should have a pH level of 7. The values of 7 is neutral on the pH scale.
What jobs require the use of a pH scale?
Soil pH - gardener, landscaping etc. Water pH - pool cleaning, public pools, water board, food industry Chemical pH - anything to do with science
Pure water has a pH of 7?
Yes and no. Pure water at 25°C has a pH of 7.0. However, water autoionises, that is splits into H+ (in the form of H3O+) and OH- spontaneously. This process is accelerate by increased temperature, that is, occurs more readily at higher temperature. Therefore at a higher temperature there will me more H+ and OH- in solution (always in equal proportions). As pH is a measure of the amount of H+ in solution, as the temperature increases, the pH will lower (lower pH means more H+). i.e. at 37°C the pH of pure water, the same water as above, will be 6.81. This water will not be acidic though, as the OH- concentration has increased by the same amount, it's just that pH only measures the pH concentration. Conversely, cool the water, and the pH will go up, 7+ for same reasons.
Why is the pH of water 7?
The pH of distilled water is 7. Seven denotes "neutral" on a pH scale, meaning it is neither acidic, nor basic. The reason for this is that there are the same number of H+ ions and OH- ions, thus keeping a balance. The importance of distilled water is that it does not contain any other chemicals which could upset this balance.
