Distilled water is typically measured to have a pH level close to 7, indicating neutrality. However, due to the dissolution of atmospheric carbon dioxide, distilled water can have a slightly acidic pH of around 5.6. This phenomenon is influenced by the partial pressure of carbon dioxide in the atmosphere and the temperature of the water. Distilled water’s pH may also vary depending on the presence of impurities or storage conditions, as prolonged exposure to air or plastic containers can alter its pH level.