Is it an acid or a base?

[Shirley Liu 2I]

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

[Mahir_Hasan2C]

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]

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]

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

[Karina Jiayu Xu 4E]

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]

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]

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

[505211599]

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

[Timothy_Yueh_4L]

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.