Carbonic acid (CO2) is a chemical compound consisting of carbon and oxygen. It is formed by combining carbon dioxide (CO2) with water (H2O) and forms a weak acid. Carbonic acid is also what makes carbonated drinks such as lemonade, mineral water or soda water fizzy.
Carbonic acid is important in water analysis because it affects the pH value of water. When carbon dioxide is dissolved in water, it reacts with water to form carbonic acid, which lowers the pH value. A higher concentration of carbon dioxide in water leads to a lower pH value and thus to more acidic water.
Free carbonic acid plays a central role in the softening and deacidification of water. It influences the carbonate hardness and the balance between dissolved CO₂, hydrogen carbonate and carbonate. The correct setting is important for the stability of the water (prevention of limescale deposits or corrosion).
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Duroval CO₂ Test Kit by Heyl – CO₂ Measurement Made Easy Quick Determination of Dissolved CO₂ The Duroval CO₂ test kit is designed for determining dissolved carbon dioxide in water samples. With this kit, you can reliably measure free carbonic acid in water using drop titration. Quick and Reliable Determination of Dissolved CO₂ in Water The Duroval CO₂ test kit enables precise measurement of dissolved carbon dioxide (free carbonic acid) in water samples. Using the proven drop titration method, CO₂ levels can be determined quickly, easily, and reproducibly. The kit is ideal for applications in water treatment, drinking water monitoring, industry, and technical operations where CO₂ content directly affects water chemistry and material durability. Why Measuring Carbon Dioxide (CO₂) in Water is Important Dissolved carbon dioxide significantly affects the pH, corrosiveness, and chemical stability of water. Excess CO₂ can cause corrosion in pipes, fittings, and system components, especially metallic materials. Additionally, CO₂ plays a key role in the lime-carbonic acid equilibrium. Imbalances can promote both scaling (lime deposits) and material degradation. Regular measurement of free CO₂ allows for targeted water treatment, optimized dosing, and prevention of system damage. The Duroval CO₂ test kit therefore supports safe process management, stable water quality, and long-term protection of water-carrying systems. Frequently asked questions How long do Heyl chemicals last? The shelf life is printed on the label of each product. Upon delivery, the guaranteed shelf life is at least 7 months. Can Heyl reagents also be purchased individually? That depends on the specific item to be ordered. For Testoval products, only the complete refill pack can be ordered. The individual small bottles cannot be reordered separately. For the Duroval test kit, the individual components of the refill pack can also be reordered separately. Can the indicator and titration solution be purchased separately? Yes, this is possible for the Duroval product range. Where can I find the safety data sheet? The safety data sheet can be found directly with the product in our shop or separately in the download area under the relevant heading. How can the chemicals be disposed of? Disposal instructions can be found in section 13 of the safety data sheet. Disposal must be carried out in accordance with official regulations. Can the chemicals still be used after the expiry date? No, the chemicals can no longer be used after the expiry date. After the expiry date, accurate measurement results can no longer be guaranteed. How should Heyl chemicals be stored? Section 7 of the safety data sheet contains all relevant information on the storage of chemicals. The recommended storage temperature should be between 15-25°C.