Ion Trends

[Emma Healy 2J]

What are some of the ion trends that we should know? And could someone please explain the ionic radius trend?

[Lucy Wang 2J]

I think you should know trends for ionization energy, electronegativity, atomic radius.

i'm not really sure about any others

[Savana Maxfield 3F]

As you move down a group, ionic radius increases. As you move across a period, ionic radius decreases.

[Jessica Manriquez 1H]

https://sciencenotes.org/periodicity-de ... chemistry/
the main picture in this website really helped me memorize the trends; Hope this helped :)

[LarisaAssadourian2K]

The previous posts are correct, but you should also know about electron affinity, which increases as you go up the periodic table and to the right.

[Gabe_Ek 1G]

I think the atomic radius trend Is a trend we should know but I am not sure about the Ionic trend. But for the ionic radius, it decreases across a period and down a group the ionic radius increases.

[George_Yin_3I]

First you have to remember the ionic radius, which is similar to atomic radius principle.

[George_Yin_3I]

The special case in ionic radius is regarding radius comparison among isoelectronic ions, in which cations are smaller than anions due to the larger proton number and greater effective nuclear charge.

[George_Yin_3I]

Besides ionic radius, I believe electron affinity, (first) ionization energy, and electronegativity are some other important properties.

[Taha 2D]

cations are smaller than their atoms(they lose their valence shell)
anions are larger than their atoms
size increases down the group and decreases across

[Neel Sharma 3F]

Atomic radius: Increase down a group, decrease across a period.
Ionic radius: Increase down a group, decrease across a period (diagonal relationships) with cations decreasing in size as they become ions and anions increasing in size.
Hope this helps!

[nayha a 1E]

Ionic radius and atomic radius follow the same general trend of increasing down a group and decreasing across a period. On the other hand, electronegativity increases across a period and decreases down a group. A general trend is that high electronegativity=high electron affinity.

[Melanie Krahn 1C]

Are there any notable exceptions to the "trends" that we should be able to memorize and know off-hand without relying on looking at the periodic table?

[Lauren Mungo 1K]

Radius increases down a group and decreases across a period. Ionization energy and electron affinity increases across a period and decreases down a group. Anions have a greater radius and cations have a smaller radius.

[rita_debbaneh2G]

The ion related trends are as follows. When you move from top to bottom of the periodic table, the ionic radius decreases, the ionization energy decreases, and electronegativity decreases. Moving from left to right shows that ionic radius increases, ionization energy increases, and electronegativity increases.

[Micaela Estavillo]

Atomic radius:
Decrease across
Increase down
Electron Affinity, Ionization Energy, and Electronegativity:
Increase across
Decrease down

[Melissa Solis 1H]

I agree with everyone else!

Focus on:
Atomic radius, which increases down while it decreases across
Electron Affinity, Ionization Energy, and Electronegativity, which increase across in a diagonal direction and decrease diagonally.

[Muskaan Abdul-Sattar]

Atomic radius, electronegativity, and ionization energy are probably important ones to know! There are periodic tables that you can look up online with trends outlined on them.

[Jaclyn Schwartz 1I]

I agree with everyone! I would probably say electronegativity would be the most important but Atomic radius, electron affinity, and ionization energy are important as well. But instead of trying to just memorize trends, try to think of why that trend occurs.

For atomic radius it increases as you go down the periodic table because more valence shells increases the size and it decreases as you go across from left to right because of the electron attraction to the nucleus grows stronger, pulling in the electrons closer to the nucleus.

For the ionization energy it increases left to right because more energy is needed to remove the electrons from their valence shells. Like in group 1 and 2, they have low ionization energy because they give their electrons, often becoming cation. And in group 7, they have high ionization energy because they only need one more electron to form an octet. Electronegativity and electron affinity follow this trend as well.

I hope this helps you memorize it little better!

[Andrea_Perez_2F]

The ionic radius trend is the concept or idea that the ionic radius of elements follows a trend going across the periodic table. So it increases when you move from top to bottom and decreases when you move from left to right.

[Alejandro Oliva 2F]

Ion trends are a very helpful way of getting an understanding of the periodic table. I like to use this visual as it depicts some of the major trends that should be recognized on the table.

IONtrends.png (8 KiB) Viewed 1134 times

These include:
Ionization Energy: Increasing Left --> Right & Down --> Up
Electron Affinity: Increasing Left --> Right & Down --> Up
Atomic Radius: Decreasing Right --> Left & Up --> Down
Nonmetallic Characters are towards the upper right
Metallic Characters are towards the bottom left

[Wenhan Li_3d]

Personally I feel like the electron affinity and electronegativity are the most important two, but ionization might should also be aware.

[Arshaun Faraji 2H]

As the ionic radius increases, you move down the group. On the other hand, as the ionic radius decreases, you move to the right in the period.

[Monse Mata 3D]

Hey! Atomic radius trend on the periodic table is bigger as you go from right to left and down. There are a few images on Google that I find helpful to have handy, that show sizes of atoms that are not to scale obviously but it allows you to see which elements have a bigger atomic radius and such.

[305561744]

To my understanding, ionic trends behave the way they do because once an atom reaches ionization, it comes down to the number of protons which determines the trend, seeing as the electrons are equal.

[Dillon Taing 3H]

Ionic trends that you should know are that ionic radius increases going down a group (from added shells) and decreases going left to right on a period (added protons attracts electrons).

[Arshaun Faraji 2H]

The main things are electron affinity, atomic radius, electronegativity, and ionization energy. If you get those down you should be good.

[Emily2J]

I would imagine we need to know:
Atomic radius
Electron Affinity
Ionization Energy
Electronegativity

definitely know the definitions of each of them and how they relate (just helps in understanding the concepts better)

[Angela Harrington 2L]

The main trends that you should know are atomic radius, ionization Energy, electron affinity, and electronegativity.