Which weight must be determined before weighing a wet sample in a moisture test?

To accurately conduct a moisture test on a wet sample, it is essential to determine the tare weight of the weigh pan. The tare weight is the weight of the empty container or pan that holds the sample. By knowing this weight, you can subtract it from the total weight of the container with the wet sample inside. This calculation allows you to isolate the weight of just the wet sample, which is critical for determining the moisture content accurately.

Understanding the tare weight is foundational in laboratory practices, as it ensures that subsequent measurements reflect only the mass of the material being tested, free from any additional weight contributed by the container. This accurate measurement is crucial for later calculations that involve the moisture content of the sample, ensuring compliance with testing standards and the reliability of results.