Questions: Fill in the left side of this equilibrium constant equation for the reaction of nitrous acid (HNO2) with water. =Ka

Transcript text: Fill in the left side of this equilibrium constant equation for the reaction of nitrous acid $\left(\mathrm{HNO}_{2}\right)$ with water. \[ \square=K_{\mathrm{a}} \]

Solution

Solution Steps

Step 1: Identify the Reaction

The reaction of nitrous acid (HNO$_2$) with water can be written as: \[ \mathrm{HNO}_2 + \mathrm{H}_2\mathrm{O} \rightleftharpoons \mathrm{H}_3\mathrm{O}^+ + \mathrm{NO}_2^- \]

Step 2: Write the Equilibrium Expression

The equilibrium constant expression for this reaction, $K_a$, is given by the concentrations of the products over the reactants. For the reaction: \[ \mathrm{HNO}_2 + \mathrm{H}_2\mathrm{O} \rightleftharpoons \mathrm{H}_3\mathrm{O}^+ + \mathrm{NO}_2^- \] The equilibrium constant expression is: \[ K_a = \frac{[\mathrm{H}_3\mathrm{O}^+][\mathrm{NO}_2^-]}{[\mathrm{HNO}_2]} \]

Step 3: Fill in the Left Side of the Equation

The left side of the equilibrium constant equation should be the expression derived in Step 2.