Page 1 of 1

Strength of acid

Posted: Fri Dec 07, 2018 5:56 pm
by hanna_maillard3B
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 ?

Re: Strength of acid

Posted: Fri Dec 07, 2018 6:01 pm
by 305144105
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.

Re: Strength of acid

Posted: Fri Dec 07, 2018 8:04 pm
by 105002507
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

Re: Strength of acid

Posted: Fri Dec 07, 2018 9:40 pm
by Daniel Bowen 3I
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.

Re: Strength of acid

Posted: Fri Dec 07, 2018 10:18 pm
by 305117729
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.