Here is a list of 0.300 M solutions that you can consider to select which has the highest concetration of potassium ions:
Select one:
a. potassium oxide
b. potassium phosphate
c. potassium hydrogen carbonate
d. potassium hypochlorite
e. potassium iodide
Answer:
- <em><u>Option b. potassium phosphate</u></em>
Explanation:
First, you must write the chemical formula of each one of the potasssium compounds. Then, assume all the compounds ionize 100%.
Since all the solutions have the same concentrations, by assuming 100% ionization, the ionization equations will show which one produces the highest number of <em>potassium ions</em>, K⁺¹, and that is the solution with the highest concentration of such ions.
<u>1. Chemical formulae</u>
Compound Formula
a. <em>potassium oxide </em> K₂O
b. <em>potassium phosphate</em> K₃PO₄
c. <em>potassium hydrogen carbonate</em> KHPO₃
d. <em>potassium hypochlorite </em> KClO₄
e. <em>potassium iodide </em> KI
<u>2. Dissociation (ionization):</u>
- a. <em>potassium oxide</em>, K₂O
K₂O does not dissociate but react with water to product KOH, then KOH dissociates, but there is not such thing as a 0.300 M solution of K₂O.
- b. <em>potassium phosphate</em>:
K₃PO₄ → 3K³⁺ + PO₄¹⁻ 3 K⁺¹ ions per unit formula
- c. <em>potassium hydrogen carbonate</em>
KHPO₃ → K⁺¹ + HPO₃⁻¹ 1 K⁺¹ ion per unit formula
- d. <em>potassium hypochlorite </em>
KClO₄ → K⁺¹ + HClO₄⁻¹ 1 K⁺¹ ion per unit formula
- e.<em> potassium iodide</em>
KI → K⁺¹ + I⁻¹ 1 K⁺¹ ion per unit formula.
Hence, the 0.300 M solution of potasssium phosphate produces the highest concentration of potassium ions.
