Problem 21 - Chemistry and Chemical Reactivity

Question

Write a balanced equation for the reaction of barium hydroxide with nitric acid.

Step-by-Step Solution

Answer

\( \text{Ba(OH)}_2 + 2\text{HNO}_3 \rightarrow \text{Ba(NO}_3 ext{)}_2 + 2\text{H}_2\text{O} \) is the balanced equation.

Step 1: Write down the reactants

Barium hydroxide is represented as \( \text{Ba(OH)}_2 \), and nitric acid is represented as \( \text{HNO}_3 \). These are the starting reactants for the chemical equation.

Step 2: Predict the products

In a reaction between an acid and a base, a salt and water are typically formed. Here, the acid is neutralized by the base. The salt formed is barium nitrate, represented by \( \text{Ba(NO}_3 ext{)}_2 \), and the water molecule is \( \text{H}_2\text{O} \).

Step 3: Write the unbalanced equation

Set up the chemical equation with the reactants and the predicted products: \( \text{Ba(OH)}_2 + \text{HNO}_3 \rightarrow \text{Ba(NO}_3 ext{)}_2 + \text{H}_2\text{O} \).

Step 4: Balance the equation

To balance the equation, ensure that there are the same number of each type of atom on both sides of the equation:1. There are 2 nitrate ions needed to balance with one barium ion, so we write 2 in front of \( \text{HNO}_3 \).2. This adjustment gives us 2 hydrogen and 2 nitrate ions as reactants.3. To balance the number of hydrogen atoms, we need 2 molecules of water because each \( \text{H}_2\text{O} \) contributes one oxygen to balance the hydroxide ions from barium hydroxide.The balanced equation is: \[ \text{Ba(OH)}_2 + 2\text{HNO}_3 \rightarrow \text{Ba(NO}_3 ext{)}_2 + 2\text{H}_2\text{O} \]

Key Concepts

Acid-Base Reactions

Acid-base reactions are chemical processes that occur when an acid reacts with a base. In these reactions, acids tend to donate protons (hydrogen ions, or H⁺), while bases accept these protons. The result is the formation of water and a salt. The general form of an acid-base reaction can be written as:

• Acid + Base → Salt + Water

A classic example involves hydrochloric acid (\( \text{HCl} \)) and sodium hydroxide (\( \text{NaOH} \)), forming sodium chloride (\( \text{NaCl} \)) and water (\( \text{H}_2\text{O} \)).

• The key outcome of these reactions is the neutralization of the acid's protons by the base's hydroxide ions, leading to water formation.
• A salt forms when the positive ion from the base combines with the negative ion from the acid.

Understanding the balanced chemical equations of these reactions is crucial for predicting the quantities of substances involved and ensuring that the law of conservation of mass is upheld.

Barium Hydroxide Reactions

Barium hydroxide, represented by \( \text{Ba(OH)}_2 \), is a strong base used in various chemical reactions. In an acid-base reaction, it readily reacts with acids to form a salt and water. When barium hydroxide reacts with acids, it follows the basic principle of acid-base reactions we discussed earlier.

• In reactions with acids like nitric acid, barium hydroxide donates hydroxide ions (\( \text{OH}^- \)) which combine with hydrogen ions from the acid to produce water.
• The remaining ions from the acid and base form a salt. In our example, the reaction with nitric acid produces barium nitrate, \( \text{Ba(NO}_3{)}_2 \).

Before writing the balanced equation, always start by predicting the products based on the knowledge of common products in strong base-acid reactions, namely water and a salt.
Barium hydroxide particularly is known for its applications that necessitate strong alkaline conditions, which are crucial in laboratory experiments and industrial processes.

Nitric Acid Reactions

Nitric acid, given by \( \text{HNO}_3 \), is a strong acid commonly involved in a wide range of chemical reactions, including acid-base reactions. When it reacts with bases like barium hydroxide, it typically results in the formation of a nitrate salt and water.

• As a versatile reactant, nitric acid plays a key role in manufacturing fertilizers, explosives, and in other industrial processes.
• In an acid-base reaction, the acid releases hydrogen ions which neutralize the hydroxide ions from the base.
• The nitrate ion from \( \text{HNO}_3 \) combines with the cations of the base to form a salt, in this case, \( \text{Ba(NO}_3{)}_2 \).

It's important to ensure that the chemical equation for this type of reaction is balanced, reflecting the conservation of mass, where the number of each type of atom is equal on both the reactant and product sides of the equation. Nitric acid's role in corrosion and explosive reactions also makes understanding its reactions crucial for safety and chemical manufacturing.