Strength of acid

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hanna_maillard3B
Posts: 61
Joined: Fri Sep 28, 2018 12:23 am

Strength of acid

Postby hanna_maillard3B » Fri Dec 07, 2018 5:56 pm

Why is it that when comparing strength of an acid (acidity) that the lower the element is in a group, the more acidic it is in a compound ?

305144105
Posts: 32
Joined: Thu May 10, 2018 3:00 am

Re: Strength of acid

Postby 305144105 » Fri Dec 07, 2018 6:01 pm

As you move down a group, the number of valence shells increase. More valence shells result in a higher shielding effect. Thus, the valence electrons feel a weaker pull from the nucleus, and they are able to more easily dissociate. This results in a stronger acid, as stronger acids dissociate more easier/completely.

105002507
Posts: 30
Joined: Fri Sep 28, 2018 12:15 am

Re: Strength of acid

Postby 105002507 » Fri Dec 07, 2018 8:04 pm

Moving down a group there is an increase in the number of valence shells = higher shielding effect. This means that the valence e-s feel a weaker pull from the nucleus and can easily dissociate = stronger acid

Daniel Bowen 3I
Posts: 32
Joined: Fri Sep 28, 2018 12:24 am

Re: Strength of acid

Postby Daniel Bowen 3I » Fri Dec 07, 2018 9:40 pm

Acid strength is based on how easily an atom can dissociate its electrons, as you go down a group there is more valence rings which allow for easier dissociation because the valence shell is farther away from the protons.

305117729
Posts: 30
Joined: Fri Sep 28, 2018 12:16 am

Re: Strength of acid

Postby 305117729 » Fri Dec 07, 2018 10:18 pm

Elements that down the group are generally larger in ionic radii, so the attraction from the nucleus will be weak, and the acids formed by these elements will be easily dissociated in water.


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