Anion Vs Cation

Anion: The Ion that is negatively charged and attracted to the anode (Positive electrode) in electrolysis is Anion.  Example: (O2-), sulfide (S2-), fluoride (F-), chloride (Cl-), bromide (Br-), iodide (I-), nitride (N3-) and hydride (H-)
Cation: The Ion that is Positively charged and attracted to the Cathode (Negative electrode) in electrolysis is Cation.  Examples: Na (+), Fe (+)

Gauge Pressure, Atmospheric Pressure, Negative Pressure and Absolute Pressure

Relation of Gauge Pressure, Atmospheric Pressure, Negative Pressure and Absolute Pressure:
Absolute Pressure = Atmospheric Pressure + Gauge Pressure
Gauge Pressure = Absolute Pressure - Atmospheric Pressure
Negative/ Vacuum Pressure = Atmospheric Pressure - Absolute Pressure
Pressure can be expressed as
Bar, Kgf/cm2/ Pa, Mpa, mm Hg, cm Hg, mH2O, m Hg, psi

Different Machine Parts in the Industry