Which statement is true about sodium hydroxide (naoh)? a. it is a salt because it increases the concentration of metallic ions. b. it is a salt because it is formed by the reaction of an acid and a base. c. it is a base because it increases the concentration of hydrogen ions. d. it is a base because it increases the concentration of hydroxide ions.

D. It is a base because it increases the concentration of hydroxide ions.

Explanation:  A base is a substance which  dissociates to give hydroxide ions in water.

An acid  is a substance which  dissociates to give hydrogen ions in water.

So is a base as it gives ions when dissolved in water.

have a great day because if you dont you and i will be sad

geosphere and hydrosphere.

this is because the geosphere has to do with geological events, while the hydrosphere controls all water on earth.