The force developed by the planet to attract a body and the magnitude of that force is called weight . The concept is also used as a synonym for dough (which, in reality, is the amount of matter that houses a body, regardless of the force of gravity).
Atomic , on the other hand, is an adjective that refers to what is linked to atom . Atoms are the smallest indivisible particles that have autonomous existence.
These definitions help us understand the idea of atomic weight , an amount that reveals the link between the mass of an atom of a specific class of isotope and 1/12 of the mass of an atom of carbon-12 .
This magnitude, which is also known as relative atomic mass , is expressed in atomic mass units . It is important to differentiate between the relative atomic mass or atomic weight and the atomic mass (which refers to the mass of each individual atom).
What the atomic weight allows is to assign a number to the chemical elements to indicate what the mass of their atoms have on average. The atomic weight will be determined according to the proportions of the isotopes, since the same chemical element can have more than one type of isotope.
An atomic weight can be calculated from the known value of the atomic mass and according to the composition of the isotopes. The result of these operations is usually reflected in the so-called periodic table of the elements.
It should be mentioned that in the scientific field, the use of the name "atomic weight" has been especially controversial . In general, scientists prefer to refer to this concept as "relative atomic mass" which, as mentioned above, should not be confused with atomic mass. To justify this decision, they explain that this property is not a weight but the force that, in a gravitational field, is exerted on a given object and that is measured in some unit of force, such as the newton.
On the other hand, those scientists who agree to refer to the concept by the name of atomic weight indicate, among other things, that it is about the denomination that he has continuously received since 1808 , when the English chemist John Dalton conceptualized it for the first time. Two centuries is too long to eradicate its use based simply on issues semantics , since you can accept the inaccuracy of the name and not allow that to generate confusion about what it represents.
Other points that support the use of atomic weight are the following:
* although for a long time the atomic weight was measured through gravimetry (also called gravimetric analysis), a method that carries the regret action, that this has changed does not justify the modification of the name originally assigned to the concept of this quantity physical;
* the name "relative atomic mass" should be reserved for the mass of an isotope (or specific nuclide);
* There are several examples of names of physical quantities that do not adequately represent their meaning, as is the case with power decisive, the molar concentration and the electromotive force, which are not force or power or molar quantity, respectively.
Finally, being truly meticulous it can be argued that atomic weight is not really "atomic", since it does not refer to a single atom. Of course, the same can be argued to the detriment of the use of "relative atomic mass" when referring to the same concept.
East phenomenon Badly awarded names also take place outside of science and, likewise, generates divisions in the academic field. However, the denomination chosen in no way reflects the skill of a scientist, but a personal preference that can respond, for example, to a need to order the concepts in his mind in a certain way.