Atomic Radii

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Sophia Dinh 1D
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Joined: Thu Jul 25, 2019 12:15 am

Atomic Radii

Postby Sophia Dinh 1D » Mon Oct 21, 2019 5:28 pm

Why does atomic radii decrease even though the number of protons increase as you go across a period?

Vanessa Chuang 4F
Posts: 51
Joined: Sat Aug 24, 2019 12:18 am

Re: Atomic Radii

Postby Vanessa Chuang 4F » Mon Oct 21, 2019 5:32 pm

The atomic radius actually decreases across a period because the number of protons increases. The increase in number of protons increases the nuclear charge (basically makes the positive charge in the nucleus more intense) and thus because of electrostatic attraction, the protons will pull in the electrons even closer, resulting in a smaller radius.

Verity Lai 2K
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Joined: Sat Aug 24, 2019 12:18 am

Re: Atomic Radii

Postby Verity Lai 2K » Mon Oct 21, 2019 5:33 pm

The atomic radii decreases because since there is more protons, there is a stronger pull on the electrons towards the nucleus. All of the elements in that period have the similar electron configurations so the added protons attract the electrons more, creating a smaller atomic radii.

selatran1h
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Joined: Fri Aug 30, 2019 12:16 am

Re: Atomic Radii

Postby selatran1h » Mon Oct 21, 2019 9:08 pm

Atomic radii decreases across a period since electrons are located in the same shell and the increasing number of protons increases the nuclear charge, pulling the electrons towards the nucleus to decrease the radius.

Jamie Lee 1F
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Joined: Fri Aug 09, 2019 12:16 am

Re: Atomic Radii

Postby Jamie Lee 1F » Mon Oct 21, 2019 9:51 pm

The more protons that are located in the nucleus, the stronger the pull is for the electrons, so the electrons are "geographically" much closer to the center of the atom.

Abigail Sanders 1E
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Joined: Wed Sep 11, 2019 12:16 am

Re: Atomic Radii

Postby Abigail Sanders 1E » Mon Oct 21, 2019 10:08 pm

Atomic radii decrease as you go across a period in the periodic table as the increased amount of protons in the nucleus has a stronger pull on the electrons. This stronger pull decreases the size of the radii by a very small, but quantifiable amount.

Abby Soriano 1J
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Re: Atomic Radii

Postby Abby Soriano 1J » Mon Oct 21, 2019 10:56 pm

The atomic radii decrease as you go across a period because the increased number of protons has a greater effect on the electrons around it (essentially the more protons there are, the more they pull on the electrons to move closer in, thereby decreasing the atomic radii).

Abigail Sanders 1E
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Joined: Wed Sep 11, 2019 12:16 am

Re: Atomic Radii

Postby Abigail Sanders 1E » Fri Nov 08, 2019 1:51 pm

The atomic radii decrease even though the number of protons increases as the increase in protons increases the effective nuclear charge on the electrons in the atom and pulls them in closer. This decreases the atomic radius.

Megan Jung 3A
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Joined: Thu Jul 11, 2019 12:17 am

Re: Atomic Radii

Postby Megan Jung 3A » Fri Nov 08, 2019 1:56 pm

Since there are more protons across a period, there is a larger positive charge in the nucleus that will pull the electrons in closer to the nucleus. This results in a smaller radii as electrons are more tightly held which is why the atomic radii decreases across a period.

KMenjivar_3A
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Joined: Mon Jan 07, 2019 8:05 am

Re: Atomic Radii

Postby KMenjivar_3A » Fri Nov 08, 2019 2:18 pm

As we go across the period, the atomic radius decrease because protons will be added to the element/atom. As more protons increase the more positive the nuclear charge is. As a result, electrons will be closer to the nucleus resulting it to have a smaller radius.

Rebecca Remple 1C
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Re: Atomic Radii

Postby Rebecca Remple 1C » Fri Nov 08, 2019 2:30 pm

Sophia Dinh 1D wrote:Why does atomic radii decrease even though the number of protons increase as you go across a period?

I agree with the previous responses! I wanted to add that, in general, electrons repel each other and are attracted to protons. Having more protons in the nucleus, and thus a higher/more positive charge, will draw electrons toward the nucleus and decrease the atomic radius. On the other hand, having more electron shells will cause electron-electron repulsion, which will make it easier to remove a valence electron. These rules play into a lot of periodic trends, so it's a good idea to familiarize yourself with them :) I hope this helps!


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