Why is it crucial to monitor the pH and temperature of water samples before analysis?

Monitoring the pH and temperature of water samples before analysis is crucial because these factors can significantly influence the accuracy and reliability of the analytical results. Changes in pH can affect the solubility and the chemical form of various substances in the water, potentially leading to different interpretations of the sample's composition. For instance, certain pollutants may become more or less toxic depending on the pH level of the water.

Similarly, temperature can impact the chemical reactions, solubility, and biological activity in water samples. For example, some analytical methods are sensitive to temperature variations and may yield different results if the sample is not kept at a consistent temperature. Therefore, documenting and controlling pH and temperature ensures that the analysis reflects the true conditions of the water sample, allowing for accurate assessments of water quality and compliance with environmental standards.