Question

Write the net ionic equation for the reaction of the strong electrolytes nitric acid and potassium hydroxide.

Short answer

The net ionic equation is \( H^+(aq) + OH^-(aq) \rightarrow H_2O(l) \).

Step-by-step solution

Identify the Reactants

The strong electrolytes must be identified first. In this case, they are nitric acid (\(HNO_3\)) and potassium hydroxide (\(KOH\)). These are the substances that will react with each other in the solution.

Write the Molecular Equation

Write the balanced molecular equation for the reaction: \[ HNO_3(aq) + KOH(aq) \rightarrow KNO_3(aq) + H_2O(l) \]. This equation represents the chemical change that takes place.

Dissociate the Strong Electrolytes

Strong electrolytes dissociate completely in water. So, write the ionic forms: \[ H^+(aq) + NO_3^-(aq) + K^+(aq) + OH^-(aq) \rightarrow K^+(aq) + NO_3^-(aq) + H_2O(l) \]. This expression represents all the ions present in the solution.

Cancel Out Spectator Ions

Identify ions that appear on both sides of the equation and cancel them out. Here, \(K^+\) and \(NO_3^-\) are spectator ions, so remove them to simplify the equation.

Write the Net Ionic Equation

After cancelling spectator ions, the remaining equation is the net ionic equation. It shows the actual chemical reaction taking place: \[ H^+(aq) + OH^-(aq) \rightarrow H_2O(l) \]. This represents the production of water from the reaction.

Key concepts

Strong Electrolytes

Understanding strong electrolytes is crucial for comprehending net ionic equations. These are substances that completely dissociate into ions when dissolved in water. This means that if you add a strong electrolyte to water, you'll have loose ions floating around rather than whole molecules.
Common examples include:

• Salts like sodium chloride ( NaCl )
• Strong acids like nitric acid ( HNO_3 )
• Strong bases like potassium hydroxide ( KOH )

The fact that they dissociate completely is why strong electrolytes are so important in chemical reactions. The ions are free to react with other ions in the solution, facilitating chemical changes.

Chemical Reactions

Chemical reactions involve the transformation of substances through the breaking and forming of bonds. In a net ionic equation, the focus is solely on the ions that participate in the reaction. The initial step to solving these equations is writing a molecular equation, which shows every compound intact. For example, the full molecular equation for the reaction between nitric acid and potassium hydroxide is: \[ HNO_3(aq) + KOH(aq) \rightarrow KNO_3(aq) + H_2O(l) \] This equation shows that nitric acid and potassium hydroxide react to form potassium nitrate and water. The next step is breaking down strong electrolytes into their mobile ions—this step reveals all the particles in the reaction.

Spectator Ions

Spectator ions are those that remain unchanged on both sides of a chemical equation. They don't participate actively in the reaction, but are still part of the ionic environment in the solution. Recognizing these ions helps simplify the equation down to its core chemical change.
In the reaction between nitric acid and potassium hydroxide, the spectator ions are:

• Potassium ions (K^+)
• Nitrate ions (NO_3^-)

These ions appear in identical form on both the reactant and product sides. By cancelling them out, you can focus on what's actually changing in the reaction. For this scenario, that leaves you with the net ionic equation that demonstrates the formation of water: \[ H^+(aq) + OH^-(aq) \rightarrow H_2O(l) \]This equation highlights the essence of the reaction: the creation of water from hydrogen and hydroxide ions.