Cation/Anion

[Karina Vasquez 1D]

When naming a coordination compound such as K3Fe(CN)6 how would I know which is the cation and which is the anion?

[Chem_Mod]

Look at where the species outside of the brackets occurs on the periodic table. In this case, though you have omitted the brackets in your question, K3 should be outside of the brackets. K3 appears in period 1 and thus you know it tends to lose an electron to form K+. Therefore, K is the cation and the coordinate covalent compound as a whole is the anion in this case.

[Gwynneth Orlino 1B]

In chemical formulas, the cation comes first followed by the anion. K3 is the cation and Fe(CN)6 is the anion.

[Ethan McCarthy 1F]

You can also tell which elements are prone to forming cations/anions based on their location on the periodic table. Elements on the left side typically lose electrons to reach the same valence shell as the noble gases (full valence shell). Losing electrons (which have a negative charge) results in a positive ion, which is a cation. Elements on the right side of the periodic table generally gain electrons in order to fill their valence electron shell, resulting in a negative ion (anion).

[Anokhi Patel 2B]

do we have to memorize the natural charges for each cation/ anion element, like 2+ or 1-

[Mitchell Koss 4G]

Not necessarily but it is helpful to know the common ones.

[selatran1h]

In chemical formulas, the cation is listed first and then the anion.

[MBouwman_4A]

In the chemical formula, the cation will be listed first followed by the anion.