Question

In a 1.0� 10�4 M solution of HCN(aq), identify the relative molar amounts of these species. Arrange from most to least

H2O
H3O+
HCN
OH-
CN-

Answer 1

In a 1.0 x 10-4 M solution of HCN(aq), the relative molar amounts of the species are: H3O+ > HCN > H2O > OH- > CN-.

Step-by-step explanation:

In a 1.0 x 10-4 M solution of HCN(aq), the relative molar amounts of the species can be arranged from most to least as follows:

1. H3O+
2. HCN
3. H2O
4. OH-
5. CN-

The concentration of H3O+ is the highest because it is formed from the dissociation of HCN in water, followed by HCN itself. H2O is present in excess in the solution and thus has a higher molar amount than OH- and CN-.