What is the formula of the ion formed when potassium achieves noble-gas electron configuration

Potassium is an alkali metal which means that it only needs to get rid of one electron to achieve a noble gas configuration.  Since it only needs to get rid of one electron the ion will be a cation with a charge of +1 which means the symbol will be K⁺.

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Ch4 and ph3 are both covalent since they are composed both of non-metals.    ch4 is non- polar because of  london forces and has a geometry of tetrahedral  ph3 , on the other hand, is umbrella shaped polar and has dipole-dipole intermolecular force (imf) . since ph3 is polar, it has a stronger imf