Question

Complete and balance the following neutralization reactions: (a) \(\mathrm{HNO}_{3}(a q)+\mathrm{Ca}(\mathrm{OH})_{2}(a q) \longrightarrow\) (b) \(\mathrm{H}_{2} \mathrm{CO}_{3}(a q)+\mathrm{Ba}(\mathrm{OH})_{2}(a q) \longrightarrow\)

Short answer

(a) \(2\mathrm{HNO}_3 + \mathrm{Ca(OH)}_2 \rightarrow \mathrm{Ca(NO}_3)_2 + 2\mathrm{H}_2\mathrm{O}\) (b) \(\mathrm{H}_2\mathrm{CO}_3 + \mathrm{Ba(OH)}_2 \rightarrow \mathrm{BaCO}_3 + 2\mathrm{H}_2\mathrm{O}\)

Step-by-step solution

Write the General Neutralization Reaction Equation

A neutralization reaction occurs when an acid reacts with a base to produce a salt and water. The general form of a neutralization equation is \((\text{{Acid}}) + (\text{{Base}}) \rightarrow (\text{{Salt}}) + (\text{{Water}})\). In this exercise, \(\mathrm{HNO}_3\) and \(\mathrm{H}_2\mathrm{CO}_3\) are acids, and \(\mathrm{Ca(OH)}_2\) and \(\mathrm{Ba(OH)}_2\) are bases.

Identify the Products of Reaction (a)

For reaction (a), the products are the salt calcium nitrate \(\mathrm{Ca(NO}_3)_2\) and water. The equation is:\[\mathrm{HNO}_{3}(aq) + \mathrm{Ca(OH)}_{2}(aq) \rightarrow \mathrm{Ca(NO}_{3})_{2}(aq) + \mathrm{H}_{2}\mathrm{O}(l)\]

Balance Reaction (a)

Ensure that the number of each type of atom on both sides of the equation is the same. The balanced form of reaction (a) is:\[2\mathrm{HNO}_{3}(aq) + \mathrm{Ca(OH)}_{2}(aq) \rightarrow \mathrm{Ca(NO}_{3})_{2}(aq) + 2\mathrm{H}_{2}\mathrm{O}(l)\]

Identify the Products of Reaction (b)

For reaction (b), the products are the salt barium carbonate \(\mathrm{BaCO}_{3}\) and water. The initial equation is:\[\mathrm{H}_{2}\mathrm{CO}_{3}(aq) + \mathrm{Ba(OH)}_{2}(aq) \rightarrow \mathrm{BaCO}_{3}(s) + \mathrm{H}_{2}\mathrm{O}(l)\]Be careful that \(\mathrm{BaCO}_{3}\) is insoluble, so it forms a solid.

Balance Reaction (b)

Balance the atoms in reaction (b). For the atoms to be balanced, the equation is:\[\mathrm{H}_{2}\mathrm{CO}_{3}(aq) + \mathrm{Ba(OH)}_{2}(aq) \rightarrow \mathrm{BaCO}_{3}(s) + 2\mathrm{H}_{2}\mathrm{O}(l)\]

Key concepts

Acid-Base Reactions

Acid-base reactions are fundamental chemical processes where an acid and a base interact, often resulting in the formation of water and a salt. This type of reaction is a staple in chemistry education due to its simple yet powerful demonstration of chemical interaction.
Acids, like \( \mathrm{HNO}_3 \) and \( \mathrm{H}_2\mathrm{CO}_3 \), have a common trait: they release hydrogen ions (\( \mathrm{H}^+ \)) in solution. Bases, such as \( \mathrm{Ca(OH)}_2 \) and \( \mathrm{Ba(OH)}_2 \), typically provide hydroxide ions (\( \mathrm{OH}^- \)).
During the reaction, these ions combine to form water (\( \mathrm{H}_2\mathrm{O} \)). Simultaneously, the remaining parts of the acid and base come together to create a salt. This process is a perfect match of opposites neutralizing each other, hence the name "neutralization reaction."

• The acid donates a proton (\( \mathrm{H}^+ \)).
• The base supplies a hydroxide ion (\( \mathrm{OH}^- \)).
• Together, they form water while producing a corresponding salt.

Understanding these reactions helps to comprehend broader chemical behavior exhibited in various environments, from industrial processes to biological systems.

Chemical Equations

Chemical equations are symbolic notations that represent chemical reactions. They depict the substances involved, the reactants and the products, using chemical formulas to display information concisely and accurately.
In our exercise, two reactions are shown:

• \( \mathrm{HNO}_{3}(aq) + \mathrm{Ca(OH)}_{2}(aq) \rightarrow \mathrm{Ca(NO}_{3})_{2}(aq) + \mathrm{H}_{2}\mathrm{O}(l) \)
• \( \mathrm{H}_{2}\mathrm{CO}_{3}(aq) + \mathrm{Ba(OH)}_{2}(aq) \rightarrow \mathrm{BaCO}_{3}(s) + \mathrm{H}_{2}\mathrm{O}(l) \)

Each part of these equations tells us about the reaction:
Reactants: The substances you start with.
Products: The substances produced by the reaction.
State symbols indicate the physical state of each substance, like (aq) for aqueous, (l) for liquid, and (s) for solid.
These equations also allow chemists to predict the result of chemical reactions and to calculate the amounts of different substances that will be produced or consumed.
Correctly writing these equations is a critical skill in chemistry, aiding in the comprehension of complex reactions.

Balancing Chemical Reactions

Balancing chemical reactions is about ensuring that the same number of each type of atom appears on both sides of the equation, maintaining the law of conservation of mass. When a reaction is balanced, it reflects that atoms are neither created nor destroyed in chemical processes.
Consider the initial unbalanced reactions from our solution:

• \( \mathrm{HNO}_{3}(aq) + \mathrm{Ca(OH)}_{2}(aq) \rightarrow \mathrm{Ca(NO}_{3})_{2}(aq) + \mathrm{H}_{2}\mathrm{O}(l) \)
• \( \mathrm{H}_{2}\mathrm{CO}_{3}(aq) + \mathrm{Ba(OH)}_{2}(aq) \rightarrow \mathrm{BaCO}_{3}(s) + \mathrm{H}_{2}\mathrm{O}(l) \)

To balance them, you adjust the coefficients, the numbers before the molecules, so that you have equal numbers of each atom type on both sides. After balancing, we have the final equations:

• \( 2\mathrm{HNO}_{3}(aq) + \mathrm{Ca(OH)}_{2}(aq) \rightarrow \mathrm{Ca(NO}_{3})_{2}(aq) + 2\mathrm{H}_{2}\mathrm{O}(l) \)
• \( \mathrm{H}_{2}\mathrm{CO}_{3}(aq) + \mathrm{Ba(OH)}_{2}(aq) \rightarrow \mathrm{BaCO}_{3}(s) + 2\mathrm{H}_{2}\mathrm{O}(l) \)

This process ensures that every atom that goes into the reaction comes out, maintaining mass balance, which is fundamental in real-world chemical applications.