Question #57859

1 Answer
Mar 24, 2014

Here are the definitions I use.

Explanation:

Ionization is the conversion of a neutral molecule or atom to an ion.

Thus, the conversion of an #"Na"# atom to #"Na"^+# is an ionization.

When #"HCl"# gas dissolves in water, it reacts to form separate #"H"_3"O"^+# and #"Cl"^"-"# ions.

#"HCl(g)" + "H"_2"O(l)" → "H"_3"O"^+"(aq)" + "Cl"^"-""(aq)"#

This is also a dissociation process.

Dissociation is a process in which a compound separates into two or more parts.

For example, water dissociates into hydronium and hydroxide ions.

onlinehomework.zohosites.com

When #"NaCl"# dissolves in water, it forms separate #"Na"^+# and #"Cl"^"-"# ions. This is a dissociation process.

#"NaCl(s)" → "Na"^"+""(aq)" + "Cl"^"-""(aq)"#

Here's a great video that shows how water dissolves salt.

#"N"_2"O"_4# decomposes into two #"NO"_2# molecules. This is a dissociation process.

#"O"_2"N-NO"_2 → "2NO"_2#

Dissolution is the process in which the particles of a substance move into the solvent.

The process may not involve dissociation, as in the dissolving of sugar …

Sugar dissolving
(from antoine.frostburg.edu)

… or it may, as in the case of sodium chloride.

chemistry.elmhurst.edu

Sugar does not dissociate in water, but #"NaCl"# does dissociate into ions when it dissolves.