Question

Alkalinity in water cannot be due to the presence of

A: OHonly
B: carbonate and bicarbonate
C: hydroxide and carbonate
D: hydroxide and bicarbonate​

Answer 1

Alkalinity in water is due to the presence of carbonates and bicarbonates.

• Alkalinity is the ability of water to resist acid or can be said to be a measure of the water's ability to reduce the acids present in the body. It is rated on a pH range of 0 to 14 where 0 to 6.99 is acidic, 7 neutral and over 7, up to 14 alkaline or basic.
• Water alkalinity is mainly due to the presence of carbonates (CO32−), bicarbonates (HCO3−), and hydroxides (OH-) ions. And to increase the pH of water in a natural pond we can use these salts also known as 'Liming'.

Answer 2

The alkalinity of water cannot be due to the simultaneous presence of

$OH$, $Co_{32}$, and $HCO_{3}$-ions because it is not only carbonate which occurs that causes the alkalinity.

• The alkalinity of water is due to the presence of carbonate, bicarbonate & hydroxide ion which is present in water.