Question #43a9c

Apr 12, 2016

HCl, hydrogen chloride

Explanation:

A conjugate acid is obtained, in the Brönsted-Lowry scheme, by protonating a base; chloride ion in this example. To protonate means to add a proton, i.e. an hydrogen ion ${H}^{+}$:

$C {l}^{\text{-}} + {H}^{+} = H C l$

Hydrogen chloride is a molecular gaseous substance. It can be prepared from the conjugate base $C {l}^{-}$ by adding concentrate sulphuric acid to a chloride salt and heating the mixture.

${H}_{2} S {O}_{4} \left(l\right) + N a C l \left(s\right) \to H C l \left(g\right) + N a H S {O}_{4} \left(s\right)$

$H C l \left(g\right)$ can be dissolved in water up to 36% concentration w/w. Dissolution is accompained by complete ionisation to give rise again to the conjugate base $C {l}^{-}$ (chloride) and hydrated hydrogen ions (${H}^{+}$)