Final answer:
The weld symbol in question is the Lewis electron dot diagram for hydrogen, which depicts the single valence electron of hydrogen. Since hydrogen has only one valence electron, which side the electron is shown on in the diagram is not significant.
Step-by-step explanation:
The weld symbol referred to in the question is actually not related to welding but is a reference to the Lewis electron dot diagram for hydrogen (H). The Lewis electron dot diagram aims to represent the valence electrons of an atom, and for hydrogen, this can simply be denoted by a single dot representing its one electron. No matter which side the dot is placed on when depicting hydrogen, the meaning is the same because hydrogen has only one valence electron. Therefore, the electron-dot symbol for hydrogen does not have "side" significance, and it can be drawn as H•, •H, or H • with the dot representing the lone electron in any position around the symbol for hydrogen.