Question #9be9c
1 Answer
Mar 11, 2015
The correct answer is a) hydroxide, carbonate, and hydrogen carbonate.
Alkalinity is another word for basicity (the concentration of hydroxide ions).
a) Hydroxide ions OH⁻ are the strongest base you can have in water.
Carbonate ions and hydrogen carbonate ions also react with water to form hydroxide ions.
CO₃²⁻ + H₂O ⇌ HCO₃⁻ + OH⁻
HCO₃⁻ + H₂O ⇌ H₂CO₃ + OH⁻
b) Nitric acid, phosphoric acid, and ammonium ions are all acidic. They do not contribute to the alkalinity of water.
c) Saline, calcified, and "aqueous" solutions are neutral. They do not contribute to the alkalinity of water.
d) "Acidic" alkalinity and "neutral" alkalinity are meaningless terms. A basic solution is by definition alkaline.
