Ionic Character

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Jonathan Marcial Dis 1K
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Ionic Character

Postby Jonathan Marcial Dis 1K » Mon Jun 04, 2018 11:40 am

I'd really appreciated it if someone could tell me how to determine ionic character.
For example,

which coumpound has greater ionic character...

NaBr or NaI

Thank you in advance.

kendallbottrell
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Re: Ionic Character

Postby kendallbottrell » Mon Jun 04, 2018 12:37 pm

Ionic character is determined in terms of "greater ionic character" and "lower ionic character". If a molecule has increasing or a higher difference in electronegativities, then there is a greater ionic character. If the difference in electronegativity is decreasing (becoming more similar), that means there is lower ionic character, and greater covalent character.

NaI has greater ionic character because there is a greater difference in electronegativities between Na and I, when compared to the difference in electronegativity between Na and Br. It helps to remember the trend of electronegativity on the period table, and then decide which atoms are closer together or farther apart.

YeseniaGomez_1L
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Re: Ionic Character

Postby YeseniaGomez_1L » Mon Jun 04, 2018 3:30 pm

The smaller the atomic ration and the greater electronegativity mean a greater ionic character. Since the trends for these increase as you go right and up on the periodic table you will find the elements with greater ionic character there. The person above is actually wrong because NaBr has greater ionic character.

Beverly Shih 1K
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Re: Ionic Character

Postby Beverly Shih 1K » Mon Jun 04, 2018 4:27 pm

To respond to the two replies above, the first person is correct that a greater difference in electronegativities causes a greater ionic character. In the case of NaBr vs NaI, Na has a low electronegativity, I has a high electronegativity, and Br has an even higher electronegativity. Therefore, NaBr has a greater difference in electronegativity than NaI, so NaBr has greater ionic character.
The second person is correct that you can also look at the size of the atoms, although the cation in this case (Na) is the same between NaBr and NaI. Smaller cations and larger anions pull the electrons closer to the cations, causing more covalent characteristics and less ionic characteristics. Br is a smaller anion than I, so it has less covalent characteristics and more ionic character.
I hope this helps clear things up!

Jordi M 2I
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Re: Ionic Character

Postby Jordi M 2I » Tue Nov 17, 2020 1:22 pm

Atoms that have many electrons are easily polarizable since their outer valence electrons can be distorted by a cation. These elements such as iodine(I) have increasing COVALENT character because their electrons are pulled into the shared bonding region by a cation. Therefore NaBr has greater IONIC character than NaI. Br has fewer shells of electrons and thus is less polarizable.

Binyu You
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Re: Ionic Character

Postby Binyu You » Fri Nov 20, 2020 8:43 am

I believe NaI has a higher ionic character because the difference between electronegativity of Na and I is bigger than those with Na and Br. Remember electronegativity increase to the right and decrease from up to down.

AnjikaFriedman-Jha2D
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Re: Ionic Character

Postby AnjikaFriedman-Jha2D » Fri Nov 20, 2020 9:53 am

I believe to determine ionic character you have to look at the electronegativity difference between the two elements in a bond. For instance, if you compare LiCl and NaCl, though they are both salts and have ionic bonds, NaCl is has a greater ionic character because there is a greater EN difference between Na and Cl than Li and Cl, because the valence electrons are more effectively shielded in Na contributing to a lower EN

Heidi Buri 2I
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Re: Ionic Character

Postby Heidi Buri 2I » Fri Nov 27, 2020 7:37 pm

Hi! In order to determine the ionic character of a molecule, you need to look at the electronegativity of atoms in the molecule. If there is a greater difference in electronegativity between atoms, the molecule has more ionic character. NaBr would have a greater ionic character than NaI. This is because Br has a higher electronegativity than I. The difference in the electronegativities in NaBr is higher than the difference in the electronegativities of NaI.

Andre Fabian 1F
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Re: Ionic Character

Postby Andre Fabian 1F » Fri Nov 27, 2020 11:36 pm

Hi there!

To determine the relative ionic character of an atom, we could do one of two things: generalize based on their positions on the periodic table, or subtract the electronegativities of the constituent atoms in the compounds.

Using the former justification, we can identify that Bromine is higher (in its group) compared to Iodine, and as such would be more electronegative. Thus, the difference in electronegativity between Bromine and Sodium is higher than that of Iodine and Sodium. As such, we can conclude that NaBr has greater ionic character.

Hope this helps!

105618850
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Re: Ionic Character

Postby 105618850 » Sat Nov 28, 2020 2:16 am

Ionic character depends on the difference in electronegativities. The greater electronegativity, the greater tendency to attract electrons or in other words a greater bond strength.

Namratha Gujje
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Re: Ionic Character

Postby Namratha Gujje » Sat Nov 28, 2020 12:22 pm

Determining greater ionic character can be done by seeing which molecule has the greater difference in electronegativity. The trend for electronegativity increases along a group and decreases down a period. Based on this rule, we can assume that NaBr has more ionic character as there is a larger eneg difference between the two bonded atoms.

Jasraj Parmar 3H
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Re: Ionic Character

Postby Jasraj Parmar 3H » Sat Nov 28, 2020 12:27 pm

If a molecule has greater ionic character than it has higher electronegativity. So, for NaBr or NaI, NaBr would be more ionic because it is has a higher electronegativity difference.

simona_krasnegor_1C
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Re: Ionic Character

Postby simona_krasnegor_1C » Sat Nov 28, 2020 2:35 pm

Since Br has a higher electronegativity than I, NaBr has higher ionic character due to the electronegativity difference.


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