I was looking at a chemical engineering test today, and, found that it was all maths about weights and mass. This puzzles, me, it cannot be simply that easy, can it? I mean, if it comes down to mere maths with mass, it is very easy... Now all we need for a new crop of chemical engineers is a snap to formula for all that mass rubbish and so forth, then... easy! First, I have found a semi formula - the atomic number doubled will lead to the first few digits of the atomic weight! This is definite progress, especially for the gases and liquids... Or heavier... that formula equals the right answer or it is heavier to under the next atomic number doubled. The problem is this does not work for 'heavier metals.' These go over the double, as they are metals, collecting more mass. I have found listings that go from [double plus five] to [double plus seven] then [double plus eight]. This means there must be a formula here too, as they seem to accelerate like orbital collection! There must be a similarity between [doubled proton and atomic number] for liquids and gases and orbitals for metals where the orbitals will show the jumping up and down amounts of mass and weight with maximum orbitals of a group or type?

The atomic number doubled does not usually lead to the first few digits of the atomic weight. It does for the lower atomic numbers, but starts to break up at atomic number 17 (Chlorine) (doesn't work for beryllium either). The atomic weight is the average weight of all of the isotopes (in proportion to their incidence on earth), or it can be calculated for specific isotopes by adding the atomic number (number of protons) to the number of neutrons. Protons and neutrons are approximately the same weight. The orbitals are related to electrons. they have little to do with the mass. Do you even know basic chemistry? No offense, but your observation is over 100 years old.

About as useful as knowing curb weights of motor vehicles as it relates to handling and safe driving techniques, it comes up occasionally, but is not always relevant to every day driving except to understand safe handling and cornering a large heavy truck is not the same as a small trim sports car.