Question

What is the conjugate base in equation NO2-+H2O HNO2+OH- ?

Answer 1

The conjugate base in the equation NO2- + H2O ↔ HNO2 + OH- is NO2- (nitrite ion), which forms when HNO2 (nitrous acid) donates a proton.

Step-by-step explanation:

The conjugate base in the equation NO2- + H2O ⇌ HNO2 + OH- is NO2- (nitrite ion). This is because when HNO2 (nitrous acid) donates a proton (H+), it forms the nitrite ion, NO2-, which is the conjugate base. In this chemical equilibrium, HNO2 is the conjugate acid of NO2-, and OH- (hydroxide ion) is the conjugate base of H2O (water). The formation of the hydroxide ion indicates an increase in pH, leading to a basic solution.

Answer 2

The hydroxide ion
`\rm OH^(-)` is the conjugate base in this equation.

Step-by-step explanation:

The acid and base in a conjugate pair differ only by a proton
`\rm H^(+)`. As the Bronsted-Lowry acid-base theory goes, the substance with that extra proton
`\rm H^(+)` is considered to be the acid. The other substance in the pair is considered to be the base.

In this reaction, there are two conjugate acid-base pairs:

`\rm {NO_2}^(-) + H^(+) \to HNO_2`:

• Base:
  `\rm {NO_2}^(-)`, which accepts a proton;
• Acid:
  `\rm HNO_2`.

`\rm H_2O \to OH^(-) + H^(+)`:

• Acid:
  `\rm H_2O`, which supplies a proton;
• Base:
  `\rm OH^(-)`.

By convention, an acid A reacts with a base B to produce

• a conjugate base of A, and
• a conjugate acid of B.

In other words,

`\text{Acid A} + \text{Base B} \to \text{Conjugate Base of A} + \text{Conjugate Acid of B}`.

For this reaction,

• Acid A is
  `\rm H_2O`, and
• Base B is
  `\rm {NO_2}^(-)`.

On the right-hand side of the equation:

• The Conjugate Base of A is
  `\rm OH^(-)`, and
• The Conjugate Acid of B is
  `\rm HNO_2`.