Ionic Radius

[nixon13]

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Do anions or cations have larger radiuses?

 

[jdent]

more electrons the bigger the radius. Do the rest of the math.....

 

[chessxwizard]

Are you talking about anions and cations of the same element? Anions generally have greater radii. Think of it as adding another electron to a "shielded" atom, basically adding thickness to the electron cloud. Cations have less of the padding, and thus a smaller radius.

 

[nixon13]

doesnt make sense to me because more electrons would cause a stronger attraction between the positive nucleus and the electrons thus making it smaller. can you explain please?

 

[jdent]

well the anion of an element has the same amount of protons as the regular element. Your only adding electrons. Therefore the negative charge will be greater than the positive anyway. The + wont be able to pull so many - to the center.

 

[osimsDDS]

Anions have a larger radius than Cations yes, that is correct... this is because cations form from the left side of the periodic table (usually metals) therefore you are losing an electron and it will be smaller because you have more protons holding onto less electrons which makes the radius smaller...

Now Anions are formed from the right side of the periodic table (usually non-metals such as halogens) and therefore they gain electrons to get octet. Therefore, they when your adding electrons the radius will become larger...

Its good to understand the concept but really more + charge will have a smaller radius than more - charge...

ex/ F- is larger than Al3+

 

[Albuterol]

Are you talking about anions and cations of the same element? Anions generally have greater radii. Think of it as adding another electron to a "shielded" atom, basically adding thickness to the electron cloud. Cations have less of the padding, and thus a smaller radius.

👍 right on!

 

[nixon13]

got it thanks again...watch for my posts im sure ill have many more questions throughout the day.