This difference may seem like a minor thing, but in certain circumstances it can be very important. For instance, let’s assume you have a sick child on your hands, and you need to give them antibiotics. You need to put the antibiotics into a fluid, preferably a sweet one so they’ll actually swallow the medicine. That’s not something you want to have an inaccurate measure of.
Weighing liquids is a relatively easy process when using an analytical balance. The first step is procuring the necessary equipment for weighing, like containers of the right size for the balance – you don’t want to use containers that can overload the balance. Then the liquids to be weighed must be prepared. Some liquids are volatile – that is, their mass changes rapidly when their temperature changes. These liquids must be weighed in a vessel like an Erlenmeyer flask which is sealed with a stopper after pouring to prevent evaporation.
Once this step is complete, the weighing container is placed on the balance. Then the tare key is pressed; the weight of the container is no longer indicated. The liquid is then carefully poured into the weighing container. The weight is then recorded, and the procedure is over.
When weighing liquids that are extremely toxic or corrosive, a spill can potentially damage or even destroy the balance. In instances like this, it is best if the liquid is poured into the container away from the balance. Tare the balance, and then record the weight of the weighing container. Then remove the container and add the liquid sample. Then tare the balance again, place the container on the balance and record the weight. Subtract the weight of the empty container from the weight of the filled container and you have your sample size.