Anions and Cations

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Anions and Cations

Postby EthanPham_1G » Fri Nov 01, 2019 1:09 pm

Why are anions larger than cations?

Charysa Santos 4G
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Re: Anions and Cations

Postby Charysa Santos 4G » Fri Nov 01, 2019 1:11 pm

Anions are generally larger than its corresponding neutral atom because adding electrons increases the number of electron-electron repulsion interactions that take place. Cations are smaller than the corresponding neutral atoms, since the valence electrons, which are furthest away from the nucleus, are lost (there is less repulsion between the electrons).

Rory Simpson 2F
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Re: Anions and Cations

Postby Rory Simpson 2F » Fri Nov 01, 2019 1:14 pm

Anions would be larger because the extra electrons would cause greater electron-electron repulsion in the atom and would decrease the effective nuclear charge. Cations would be the opposite, since less electrons means less electron-electron repulsion.

MingdaH 3B
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Re: Anions and Cations

Postby MingdaH 3B » Fri Nov 01, 2019 1:21 pm

Anions are larger because they have more electrons than cations. These extra electrons may be part of additional shells, which would significantly increase the size, or they may just add more electron - electron repulsion forces, which would somewhat increase the size of the atom.

Hannah Romano 4D
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Re: Anions and Cations

Postby Hannah Romano 4D » Fri Nov 01, 2019 1:30 pm

cations, especially in groups 1 and 2, will become significantly smaller because they often achieve +1 and +2 charges respectively. When this occurs, these atoms completely lose their outer shells. Their positively charge nucleus will pull the remaining electrons extra tightly. ultimately, this results in these cations being very small.

Anna Heckler 2C
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Re: Anions and Cations

Postby Anna Heckler 2C » Fri Nov 01, 2019 2:23 pm

Cations are significantly smaller than anions because they have lost the electrons in their outermost shell. The protons in the nucleus pull the remaining electrons very tightly towards the nucleus, decreasing the atomic radius. Anions, on the other hand, gain electrons to complete their outer shell, increasing the atomic radius.

Julia Mazzucato 4D
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Re: Anions and Cations

Postby Julia Mazzucato 4D » Fri Nov 01, 2019 5:06 pm

With cations, the electrons are pulled more closely towards the nucleus because there is less electron shielding occurring. Whereas an anion, because of the additional valence electrons, have a larger outer shell.

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Re: Anions and Cations

Postby HuyHa_2H » Sat Nov 02, 2019 2:18 am

Anions gain electrons whereas cations lose electrons so basically anions get heavier and cations get lighter.

Julieta Serobyan4D
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Re: Anions and Cations

Postby Julieta Serobyan4D » Sat Nov 02, 2019 2:25 am

EthanPham_4D wrote:Why are anions larger than cations?

Anions have more electrons and it's harder for nucleus to pull them. So, the distance between the electrons and the nucleus increases.

Kaitlyn Jang 1F
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Re: Anions and Cations

Postby Kaitlyn Jang 1F » Sat Nov 02, 2019 10:19 am

Anions are larger because when adding electrons, electron-electron repulsion increases and create a larger atomic radius. Cations lose electrons from the valence shell which make them smaller in size.

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