Question

I am studying Acids & Bases. I understand that Acids ionize, creating ions that were not previously there. I understand that Bases dissociate, simply breaking the compound apart into its individual ions.

Acids ionize to create (H3O) ions by producing/donating an (H+) ion

Bases dissociate, with one ion being (OH-)

But I am confused about the Bases.... I get that the compound breaks apart, and that bases dissolve/accept protons but if you are looking at this chemical equation, which dissociates in H2O....

NaOH(aq) --> Na+(aq) + OH-(aq)................ Who does the proton accepting/dissolving becuase where do the components of H2O go? What is the acid vs. the base? I dont understand who accepts/donates what since the components of H2O dont show up in the products...

Because in weak bases,

NH3 + H2O --> <-- NH4+ + OH- ................ the NH3 accepts the (H+) ion from H2O, making NH3 the base, to create NH4 and OH-. Is H2O the acid in this equation?

I hope this makes sense haha

Answer 1

A substance can act as base due to presence of lone pair or due to presence of OH-

If OH- is present, the base is called strong base
Strong base dissociate completely in water and water here just act as solvent
It hust help in dissociating the base
NaOH ----> Na+ (aq) + OH-(aq) can happen only in water

Weak base on other hand have lone pair and this lone pair attracts H of water
this make water dissociate and take part in reaction
For example,
NH3 + H2O --> <-- NH4+ + OH-
Yes water is acid here