# Will a salt dissociate completely in water to give free ions?

I was reading salt hydrolysis of a salt made from strong acid and weak base. I came across the hydrolysis of $$\ce{NH_4Cl}$$. These reactions were mentioned

$$\ce{NH_4Cl + H_2O<=>NH_3 + HCl \tag{R1}}$$ $$\ce{NH_4+ + Cl- + H_2O<=>NH3 + H+ + Cl-}\tag{R2}$$ $$\ce{NH_4+ + H_2O<=>NH3 + H3O+\tag{R3}}$$

$$\ce{H+}$$ and $$\ce{Cl-}$$ will not combine appreciably and concentration of $$\ce{HCl}$$ cam be neglected.

But in the second reaction, why did they assume that $$\ce{NH_4Cl}$$ dissociated completely into ions in water? Is that practically true too?

Edit: I also have another question; when calculating $$\text{pH}$$ of a salt like $$\ce{NH_4Cl}$$, is the concentration of hydrogen ions, $$\ce{[H+]},$$ inclusive of the contributions from water?

• Is this supposed to be in aqueous solution? – MaxW Oct 20 '20 at 18:54
• A weak acid NH4+(aq) reacts with the strong base OH-, passing to it its proton, forming NH3(aq) and H2O. – Poutnik Oct 20 '20 at 19:36
• NH4OH does not exist. It is a solution of NH3 in water. The formula NH4OH is a wrong formula invented in the 19th century, and still printed by merchants, because the customers (caretakers and contractors) prefer this name to the name of ammonia solution . – Maurice Oct 20 '20 at 20:18