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Whether to follow a recipe or to know our weight, we require instruments to measure the mass. Everywhere in your life you come across weight or scale. Everything around us has mass and if we want to know what the weight of something is, we need a tool to measure these things. The scales or balances are instruments calibrated to be able to weigh.
The main difference is that while the scale measures weight, a scale measures mass. Weight is the force of gravity on an object, while mass determines the amount of matter in an object.
When working in a laboratory the amount of what we must think can be very small, but we must be very precise. Do you have a clue what the analytical balance is and what for it is for?
The analytical balance is an essential tool for the determination of chemicals. The precision achieved by innovation far exceed that of any other measuring instruments. The simple balance, used for weighing, was discovered before 5000 BC.
The term “balance” comes from the Latin bilanx which simply means “two saucepans”. However, modern analytical equilibrium originally comes from the middle 18th century. The founder was the Scottish chemist Joseph Black, around 1750, when he was still a student.
Initially your scale was like seesaw, a sample was placed on one tray and then a known weight was added to the other tray until a balance was established. These laboratories instrument is very sensitive. You can be in a range precision between 0,1 mg to 0,01 mg.
Modern analytical balances have glass doors that prevent air from flowing, which could disturb samples that are very small. This instrument is used to detect very fine steps, so even the slightest vibration or wind can affect the result. And since we must be very exact when weighing the substances of interest, in the laboratory we prefer to use analytical balances instead of precision balances.
Basically, balances and scales are used in laboratories with different shapes and sizes. The simplest type are spring balances, which consist of a coil spring suspended from a fixed point with a tray at the other end. On the other hand, we have beam scales, these are used to weigh solids, liquids, powders or even animals, the capacity is up to one kilogram.
Whereas, instead, analytical balances are designed for high precision in quantitative chemical analysis, performance readability with four decimal places to the right of the decimal point down to 0.0001 grams.
Therefore, we would never weigh half kilo of a substance on an analytical balance and we could not measure 0.001 grams on a scale.
How does an analytical balance work? Analytical scales measure the force required to counteract the mass of a sample rather than the actual masses. These devices use an electromagnet to generate a force to counteract the sample and generate the result by measuring the force necessary to achieve equilibrium.
Finally, I give you some advice on what to look for in an analytical balance.
It is important to consider the basic characteristics: capacity, readability, precision, functionality, sensitivity of the scales. Scales typically give weights in more than a dozen units, including grams, kilograms, pounds, newtons, grams, and ounces. The analytical balance can be connected to various devices, such as a computer, a data printer, an analytical instrument with a serial, parallel or USB cable. Even some modern models are equipped with Bluetooth technology to allow wireless communication.
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