# Problem: Rank acetic acid (HC2H3O2), hydrocyanic acid (HOCN), and hydrofluoric acid (HF) in order of increasing strength.Acid                             KaHC2H3O2                  1.8 × 10–5HOCN                        3.5 × 10–4HF                              6.8 × 10–4A) HC2H3O2 &lt; HOCN &lt; HFB) HOCN &lt; HC2H3O2 &lt; HFC) HOCN &lt; HF &lt; HC2H3O2D) HF &lt; HOCN &lt; HC2H3O2E) HF &lt; HC2H3O2 &lt; HOCN

###### FREE Expert Solution

For this problem, we have to rank acetic acid (HC2H3O2), hydrocyanic acid (HOCN), and hydrofluoric acid (HF) in order of increasing strength.

• For a weak acid HA, the acid-base reaction will appear as:

HA (aq) + H2O (l) ⇌ H3O+ (aq) + A- (aq)

• Ka expressions can be written as:

###### Problem Details

Rank acetic acid (HC2H3O2), hydrocyanic acid (HOCN), and hydrofluoric acid (HF) in order of increasing strength.

Acid                             Ka
HC2H3O2                  1.8 × 10–5
HOCN                        3.5 × 10–4
HF                              6.8 × 10–4

A) HC2H3O2 < HOCN < HF

B) HOCN < HC2H3O2 < HF

C) HOCN < HF < HC2H3O2

D) HF < HOCN < HC2H3O2

E) HF < HC2H3O2 < HOCN

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Ka and Kb concept. You can view video lessons to learn Ka and Kb. Or if you need more Ka and Kb practice, you can also practice Ka and Kb practice problems.

What is the difficulty of this problem?

Our tutors rated the difficulty ofRank acetic acid (HC2H3O2), hydrocyanic acid (HOCN), and hyd...as low difficulty.