What is the formula for hydrochloric acid? What are the symbols with oxidation numbers?

1 Answer
Nov 30, 2016

Answer:

Gaseous hydrogen chloride is represented as #HCl(g)#......

Explanation:

In water, hydrogen chloride dissolves and ionizes to form aqueous hydrogen chloride:

#HCl(g) +H_2O(l) rarr H_3O^(+) + Cl^(-)(aq)#

Oxidation number results from distribution of the charge to the most electronegative atom; here, we get #H(+I)# and #Cl(-I)#.

Undergraduate treatment:

When we write #H_3O^+#, the #"hydronium ion"#, this is more of a convenience than an actual entity. When we write #H^+# or #H_3O^+# we mean the #"acidium"# species in water, a cluster or 3 or 4 water molecules WITH an EXTRA #H^+#, i.e. #H_7O_3^+# or #H_9O_4^+#. The extra proton rapidly exhanges between clusters, and #H_3O^+# is a convenient representation.