CHEM 1413 Take-Home Assignment 3 This assignment is due 4-6-18. Name: 1. When Na
ID: 1038635 • Letter: C
Question
CHEM 1413 Take-Home Assignment 3 This assignment is due 4-6-18. Name: 1. When NaNO2, a weak base, is placed in water is dissociates into Nat and NO2. The NO2 ion then reacts with water according to the following reaction. NO2(a) + H20o HNO2(a)+OH (a) Which of the following best describes a solution prepared by dissolving sodium nitrite in water? A. Acidic, because nitric acid is created B. Acidic because hydroxide is created C. Basic because nitric acid is created D. Basic because hydroxide ion is createdExplanation / Answer
Answer 1
D) Basic because hydroxide ion is created.
Explanation=
NaNO2 = Na+ + NO2-
NO2-(aq)+ H2O(l) = HNO2(aq) +OH-(aq)
HNO2, Nitrous acid is a weak acid. It means it's tendency to furnish H+ ion is weak. In other words it will retain its H+ ion with it. So we are left with OH- ions only which renders the solution basic.
Moreover if we apply Bronsted-Lowry concept of acid base conjugate pair, we conclude that conjugate base of a strong acid will be a weak base and conjugate base of a weak acid will be a strong base. Here H2O acts as an acid since it gives hydrogen ion. Thus OH- being the conjugate base of a weak acid, it will be a strong base. Hence the result.