3rd option please and good luck hope you pass...........
Answer:
A. An identification of the atoms in a molecule
Explanation:
The chemical formula of a compound is a representation which shows all the elements therein and the mole relationship between them expressed as subscripts.
Therefore, a chemical formula allows us to identify atoms that are within a molecule.
A molecule is a covalent compound that has discrete or separate units.
For example;
HCl represents 1 mole of hydrogen chloride molecules consisting of 1 mole of hydrogen atoms and 1 mole of chlorine atoms.
The element should be Argon
28.02g ------ 1 mol
X g ------------ 4.60 mol
X = (28.02×4.60)/1
X = 128,892 g
Answer:
Both of these phenomena is due to the ignition temperature.
Explanation:
Trees don't spontaneously catch fire because there is a temperature above which materials combust. This is called the "ignition temperature." This temperature must be reached before the trees will ignite, and the external condition does not always harbor such high temperature.
Fires don't stop immediately because, while some parts of the flame has cooled down sufficiently below the ignition temperature, other parts of the flame have not. It takes time for all the part of the flame to cool down below ignition temperature for the burning to stop.