Question

1. In one step, ammonium chloride (NH4Cl) was added to lower the blood pH. The ammonium ion is what acts as the acid. The chloride ion does not have any acid/base properties.

a. Why is the ammonium ion used as the acid source instead of HCl?

b. Why is NH4Cl used instead of some other ammonium compound (such as NH4NO3 or NH4I)?

Answer 1

a. Ammonium chloride is soluble in water. When the crystals of ammonium chloride are dissolved in water, the ammonium chloride compound decomposes into its component ions: NH4⁺ and C_^l-

The acidic or the basic components of a salt can be determined only at its aqueous form by dissolving the salt in water. The acidic component is the one that produces hydrogen (H+) ions when dissolved in water. In this case, Cl- is the acidic component of NH₄Cl.

NH₄Cl + H₂O = NH₄+ + HCl

Cl- + H₂O = H+ Cl- +H₂O

The chloride (Cl-) first associates in water to form hydrochloric acid (HCl) and the dissociation of HCl produces hydrogen ions (H+).

The slightly acidic nature of ammonium chloride is due to the formation of hydrochloric acid (HCl). HCl is a strong acid and use of it may pose danger so, ammonium chloride is used as a source of acid instead of HCl.

b.Cl- ion are of greater use in the stomach (HCl is the main component of stomach acid)

On the other hand Cl- ions being smaller than nitrate and iodide ions, will be transported easier on bloodstream