Question

Write a balanced equation for the neutralization of each of the following: a. \(\mathrm{H}_{3} \mathrm{PO}_{4}(a q)\) and \(\mathrm{NaOH}(a q)\) b. \(\mathrm{HI}(a q)\) and \(\mathrm{LiOH}(a q)\) c. \(\mathrm{HNO}_{3}(a q)\) and \(\mathrm{Ca}(\mathrm{OH})_{2}(s)\)

Short answer

a. H₃PO₄(aq) + 3 NaOH(aq) → 3 H₂O(l) + Na₃PO₄(aq)b. HI(aq) + LiOH(aq) → H₂O(l) + LiI(aq)c. 2 HNO₃(aq) + Ca(OH)₂(s) → 2 H₂O(l) + Ca(NO₃)₂(aq).

Step-by-step solution

- Write the Reactants

Identify the reactants for each neutralization reaction.For part a: H₃PO₄(aq) and NaOH(aq).For part b: HI(aq) and LiOH(aq).For part c: HNO₃(aq) and Ca(OH)₂(s).

- Write the Products

Identify the products of each neutralization reaction, which are typically water (H₂O) and a salt.For part a: The products are H₂O and Na₃PO₄.For part b: The products are H₂O and LiI.For part c: The products are H₂O and Ca(NO₃)₂.

- Balance the Equations

Ensure that the number of atoms for each element is balanced on both sides of the equation.Part a (H₃PO₄ and NaOH): H₃PO₄(aq) + 3 NaOH(aq) → 3 H₂O(l) + Na₃PO₄(aq).Part b (HI and LiOH): HI(aq) + LiOH(aq) → H₂O(l) + LiI(aq).Part c (HNO₃ and Ca(OH)₂): 2 HNO₃(aq) + Ca(OH)₂(s) → 2 H₂O(l) + Ca(NO₃)₂(aq).

- Verify the Reactions

Check that the equations are properly balanced by counting the atoms for each element on both reactant and product sides.For part a: Reactants: 3 H, 1 P, 4 O + 3 Na, 3 O, 3 H. Products: 3 H₂O (3 H₂, 3 O) + Na₃PO₄ (3 Na, 1 P, 4 O).For part b: Reactants: 1 H, 1 I + 1 Li, 1 O, 1 H. Products: H₂O (2 H, 1 O) + LiI (1 Li, 1 I).For part c: Reactants: 2 H, 2 N, 6 O + 1 Ca, 2 O, 2 H. Products: 2 H₂O (2 O, 2 H) + Ca(NO₃)₂ (1 Ca, 2 N, 6 O).

Key concepts

balancing equations

Balancing equations is a crucial step in all chemical reactions. To balance an equation, ensure that the number of atoms for each element is the same on both the reactant and product sides. For example, in the neutralization of \(\text{{H}}_3\text{{PO}}_4\) and \(\text{{NaOH}}\), begin by writing the unbalanced equation: \(\text{{H}}_3\text{{PO}}_4 + \text{{NaOH}} \rightarrow \text{{H}}_2\text{{O}} + \text{{Na}}_3\text{{PO}}_4\). Here, you can see how the sodium \(\text{{Na}}\) and water \(\text{{H}}_2\text{{O}}\) molecules need to be matched.
Balance the hydrogen, oxygen, and sodium, resulting in: \(\text{{H}}_3\text{{PO}}_4 + 3 \text{{NaOH}} \rightarrow 3 \text{{H}}_2\text{{O}} + \text{{Na}}_3\text{{PO}}_4\).
Remember these tips:

• Focus on one element at a time.
• Use coefficients to balance the atoms.
• Double-check your count at the end.

acid-base reactions

Acid-base reactions are a common type of chemical reaction where an acid reacts with a base. These reactions typically produce water \(\text{{H}}_2\text{{O}}\) and a salt. The acid donates protons \(H^+\), while the base provides hydroxide ions \(\text{{OH}}^-\). For example, in the reaction between \(\text{{HNO}}_3\) and \(\text{{Ca(OH}}_2\), \(\text{{HNO}}_3\) is the acid (donates \(H^+\) ions) and \(\text{{Ca(OH}}_2\) is the base (provides \(\text{{OH}}^-\) ions). They combine to form calcium nitrate \(\text{{Ca(NO}}_3\text{{)}}_2\) and water:
\(2 \text{{HNO}}_3 + \text{{Ca(OH}}_2 \rightarrow 2 \text{{H}}_2\text{{O}} + \text{{Ca(NO}}_3\text{{)}}_2\).
This reaction is essential for understanding how acids and bases neutralize each other.

producing salts

In acid-base reactions, producing salts is a common outcome. When an acid reacts with a base, they form a salt and water. The salt consists of the cation from the base and the anion from the acid. For instance, in the reaction between hydroiodic acid (HI) and lithium hydroxide (LiOH):
\(\text{{HI}} + \text{{LiOH}} \rightarrow \text{{H}}_2\text{{O}} + \text{{LiI}}\)
The acid \(\text{{HI}}\) provides the iodide ion (I\textsuperscript{-}), and the base \(\text{{LiOH}}\) provides the lithium ion (Li\textsuperscript{+}).
These combine to form the salt lithium iodide (LiI).

• Salts are ionic compounds.
• Names of salts typically end in '-ide,' '-ate,' or '-ite.'
• The formation of salts is a key indicator of a neutralization reaction.

chemical equation

A chemical equation represents a chemical reaction using symbols and formulas. It shows the reactants and products involved in the reaction. For a neutralization reaction, the equation includes an acid and a base as reactants, and water and a salt as products. For example, consider the neutralization of \(\text{{H}}_3\text{{PO}}_4\) and \(\text{{NaOH}}\):
\(\text{{H}}_3\text{{PO}}_4 + 3 \text{{NaOH}} \rightarrow 3 \text{{H}}_2\text{{O}} + \text{{Na}}_3\text{{PO}}_4\).
Key components in a chemical equation:

• Reactants: Substances that start the reaction.
• Products: Substances formed by the reaction.
• Arrows (→) separate reactants from products.
• Coefficients indicate the number of molecules.

Understanding chemical equations helps in predicting the products and determining the quantities of reactants needed.