What are the common contaminants in chemical samples?

Common contaminants in chemical samples include dust, moisture, unwanted chemicals, bacteria, and other impurities.

Chemical samples can be contaminated by a variety of substances. One of the most common contaminants is dust. Dust particles can easily get into chemical samples if they are not properly stored or handled. These particles can alter the properties of the sample and affect the results of any tests or experiments conducted with it.

Moisture is another common contaminant. Many chemicals react with water, so any moisture that gets into a sample can cause unwanted reactions. This is particularly a problem for hygroscopic substances, which absorb water from the air. To prevent moisture contamination, samples should be stored in airtight containers and handled in a dry environment.

Unwanted chemicals can also contaminate samples. This can happen if the equipment used to handle or store the sample is not properly cleaned, or if the sample comes into contact with other chemicals. Even small amounts of unwanted chemicals can cause significant changes in a sample's properties.

Bacteria and other microorganisms are another source of contamination. These can get into samples from the air, from the equipment used to handle the sample, or from the person handling the sample. Bacteria can cause chemical changes in the sample, particularly if the sample is a biological substance.

Other impurities can also contaminate chemical samples. These can include particles of the container the sample is stored in, residues from previous samples, or substances in the air. To minimise the risk of contamination, it's important to use clean, appropriate containers for storage, and to handle samples in a clean, controlled environment.