The letter A is used as an abbreviation for atom. ATM is used to mean atmosphere.
It is also possible that someone asked wrongly and wanted to know what ATOM means as an acronym. ATOM stands for many different things, including:
It is the chemical symbol of that element. One or two characters, the first always a capital:
C for carbon, He for helium, O for oxygen, N for nitrogen, S for sulfur
Na for sodium (from Latin: natrium), Ca for calcium, etc.
Abbreviations for elements are called chemical symbols.
Lab is the abbreviation for Laboratory.
The smallest atom is hydrogen.
The symbol for the Euro is: € The standard abbreviation is: EUR
Specific
FL
[He]2s22p2
In chemistry the abbreviation amu stands for atomic mass unit. It is defined as 1/12th the mass of a carbon atom.
atom Be is the abbreviation for beryllium, a light strong brittle grey toxic bivalent metallic element having atomic number 4.
There are multiple numbers on the periodic table. The ones right under the abbreviations is the atomic weight of the atom. The number just above the abbreviation is the atomic number. Here is an example: Sodium 11= Atomic Number Na= Atom Abbreviation 22.99= Atomic weight
EN in the periodic table stands for Electronegativity. Electronegativity is a relative measure of an atom's ability to attract shared electrons to itself when it is chemically bonded with another atom.
The chemical symbol for carbon monoxide is CO.
What is the neutral atom that has its first two energy levels filled, has 5 electrons in its third energy level, and has no other electrons? Enter the name of the element, not the abbreviation.
The abbreviation is AAS.The abbreviation is AAS.The abbreviation is AAS.The abbreviation is AAS.The abbreviation is AAS.The abbreviation is AAS.
The abbreviation for abbreviation is "abbr."
The abbreviation for centimeter is cm. The abbreviation for meter is m. The abbreviation for inches is in. The abbreviation for liter is L.
If HE was a compound it would be a compound of H (hydrogen) and E (sorry there is no such element).If HE is an element then it is misspelled and should be He (helium).
"GPA" is already an abbreviation for "grade point average". There is no further abbreviation for the abbreviation.