Is it an acid or a base?

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Shirley Liu 2I
Posts: 64
Joined: Fri Sep 28, 2018 12:16 am

Is it an acid or a base?

Postby Shirley Liu 2I » Sun Jan 20, 2019 5:22 pm

When given a compound, how do we know if it will gain or lose H+ just from looking at its formula?

Mahir_Hasan2C
Posts: 60
Joined: Fri Sep 28, 2018 12:25 am

Re: Is it an acid or a base?

Postby Mahir_Hasan2C » Sun Jan 20, 2019 6:20 pm

We can tell if it donates or accepts a proton by the manner it dissociates. For example, if we were given the salt NH3Cl we would decide this is a base due to the fact that its reaction with water would produce a hydroxide concentration. I find it easier to tell if you add water to it and see whether or not it makes either a hydroxide concentration or proton concentration.

Diviya Khullar 1G
Posts: 59
Joined: Fri Sep 28, 2018 12:19 am

Re: Is it an acid or a base?

Postby Diviya Khullar 1G » Sun Jan 20, 2019 7:27 pm

Another way you can check is by drawing a Lewis structure and checking to see if it has a lone pair to which an H+ can bond or to see if it has any hydrogen atoms that the compound can easily release.

Jaqueline Monreal 2L
Posts: 57
Joined: Fri Sep 28, 2018 12:28 am

Re: Is it an acid or a base?

Postby Jaqueline Monreal 2L » Sun Jan 20, 2019 7:38 pm

an acids donates a proton H+ and a base accepts the proton

Karina Jiayu Xu 4E
Posts: 58
Joined: Fri Sep 28, 2018 12:29 am

Re: Is it an acid or a base?

Postby Karina Jiayu Xu 4E » Sun Jan 20, 2019 8:30 pm

You can also look for any part of the compound that has a strong dipole moment, bc that can usually tell you where an extra hydrogen can go

Michelle Nwufo 2G
Posts: 61
Joined: Fri May 18, 2018 3:00 am

Re: Is it an acid or a base?

Postby Michelle Nwufo 2G » Sun Jan 20, 2019 11:34 pm

I am also confused on not just determining if something is an acid or base, but determining whether or not something is a WEAK acid or base. Can any of you clarify please?

404982241
Posts: 47
Joined: Fri Sep 28, 2018 12:17 am

Re: Is it an acid or a base?

Postby 404982241 » Sun Jan 20, 2019 11:55 pm

an acid donates a proton H+
a base accepts the proton

505211599
Posts: 60
Joined: Fri Sep 28, 2018 12:28 am

Re: Is it an acid or a base?

Postby 505211599 » Sun Jan 20, 2019 11:56 pm

Acids usually donate protons (H+) while bases accept protons.

Timothy_Yueh_4L
Posts: 57
Joined: Fri Sep 28, 2018 12:28 am

Re: Is it an acid or a base?

Postby Timothy_Yueh_4L » Mon Jan 21, 2019 12:41 am

By the brosted-lowry model, a molecule is an acid if it denotes a proton and produces hydronium ions after reacting with water, and a molecule is a base if it takes a proton to produce a hydroxide ion after reacting with water. Generally if a molecule has a nitrogen atom, it's lone pair can attract a hydrogen from water which makes it a base.


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