Problem 87 - Chemistry The Central Science

Question

Write a balanced chemical reaction for the condensation reaction between \(\mathrm{H}_{3} \mathrm{PO}_{4}\) molecules to form \(\mathrm{H}_{5} \mathrm{P}_{3} \mathrm{O}_{10} .\)

Step-by-Step Solution

Answer

The balanced chemical reaction for the condensation reaction between H3PO4 molecules to form H5P3O10 is: \[ 3 \mathrm{H}_{3}\mathrm{PO}_{4} \rightarrow \mathrm{H}_{5}\mathrm{P}_{3}\mathrm{O}_{10} + 5\mathrm{H}_{2}\mathrm{O} \]

Step 1: Write the unbalanced chemical reaction

To start, we will write the unbalanced chemical equation for the condensation reaction between H3PO4 molecules to form H5P3O10: \[ \mathrm{H}_{3}\mathrm{PO}_{4} \rightarrow \mathrm{H}_{5}\mathrm{P}_{3}\mathrm{O}_{10} \]

Step 2: Identify the products and find the correct stoichiometry

We can see that the product, H5P3O10, has three P atoms in it, which means that three H3PO4 molecules must react to form one H5P3O10 molecule. The condensation reaction involves the formation of water molecules as a byproduct. In this case, it is necessary to find the correct stoichiometry: 3 H3PO4 → H5P3O10 + xH2O We can analyze this by comparing the number of H, P, and O atoms on both sides of the equation.

Step 3: Balance the H atoms

There are 15 H atoms on the left side (3 * 3 H atoms in H3PO4) and 5 H atoms in H5P3O10. To balance the H atoms, we must add "x" H2O molecules to the right side of the equation: 3 H3PO4 → H5P3O10 + xH2O Since there are 10 H atoms remaining, x = 5, since 5 H2O molecules will contain 10 H atoms: 3 H3PO4 → H5P3O10 + 5H2O

Step 4: Check the balance of P and O atoms

The P atoms are already balanced (with 3 P atoms on both sides). Now we can check for the balance of O atoms. There are 12 O atoms on the left side (3 * 4 O atoms in H3PO4) and 10 O atoms in H5P3O10. The right side of the equation also has 5 * 1 O atoms in 5 H2O molecules: 3 H3PO4 → H5P3O10 + 5H2O There are 10 O atoms in H5P3O10 and 5 O atoms in 5 H2O molecules, giving us a total of 15 O atoms on the right side of the equation, which matches the left side. Therefore, the equation is balanced.

Step 5: Final Answer

The balanced chemical reaction for the condensation reaction between H3PO4 molecules to form H5P3O10 is: 3 H3PO4 → H5P3O10 + 5H2O

Key Concepts

Condensation Reaction

Condensation reactions are interesting because they involve the joining of molecules with the removal of a smaller molecule, usually water. This type of reaction plays a critical role in various chemical processes, both in natural and synthetic systems. In the exercise given, we encounter a classic example where multiple \( \mathrm{H}_{3} \mathrm{PO}_{4} \) molecules combine to form \( \mathrm{H}_{5} \mathrm{P}_{3} \mathrm{O}_{10} \) while releasing water.
Key features of condensation reactions include:

• The formation of a new product alongside a smaller byproduct, like \( \mathrm{H}_{2} \mathrm{O} \).
• Often used in polymerization processes.
• It requires careful balancing due to the loss of atoms from the reactants as byproducts.

In the context of this exercise, understanding the removal of water is essential as it influences the stoichiometry and balancing of the equation. With every bond formed between larger molecules, small molecules like water often leave the system. This necessitates a careful accounting of all atoms involved.

Stoichiometry

Stoichiometry in chemistry is like a balancing act, ensuring that the proportions of reactants and products reflect the conservation of mass.
In our example with the reaction of \( \mathrm{H}_{3} \mathrm{PO}_{4} \) molecules, the stoichiometry determines how many of these reactants are needed to produce a certain amount of \( \mathrm{H}_{5} \mathrm{P}_{3} \mathrm{O}_{10} \).
Here's how stoichiometry helps:

• It involves counting how many of each type of atom exist on both sides of the reaction. This ensures that no atoms are lost or gained in the reaction process.
• Determines the ratio of reactants (in this case, 3 molecules of \( \mathrm{H}_{3} \mathrm{PO}_{4} \)) to products.
• Helps in identifying if all atoms are accounted for, such as the hydrogen and oxygen atoms forming water.

In our reaction, analyzing the stoichiometry allowed the correct number of \( \mathrm{H}_{2} \mathrm{O} \) molecules to be identified, ensuring a balanced reaction overall. Stoichiometry is central in predicting how much product will form from given reactants in any chemical reaction.

Chemical Reaction Balancing

Balancing chemical reactions is vital to reflect the law of conservation of mass, which states that matter cannot be created or destroyed in an isolated system. Thus, for any chemical reaction written down, the same number of atoms of each element must appear on both sides of the equation.
Let's break down the balancing process with our example:

• First, construct the unbalanced equation showing reactants and products, such as: \( \mathrm{H}_{3} \mathrm{PO}_{4} \rightarrow \mathrm{H}_{5} \mathrm{P}_{3} \mathrm{O}_{10} \).
• Identify and tally the number of atoms for each element on both sides of the equation. Pay attention to elements like hydrogen, phosphorus, and oxygen.
• Adjust coefficients to get the atoms to balance. For instance, 3 \( \mathrm{H}_{3} \mathrm{PO}_{4} \) yields the correct number of phosphorus atoms, while balancing hydrogens with water adjustment.
• Verify the equation by double-checking that each element is balanced, reaching a balanced result: \( 3\mathrm{H}_{3}\mathrm{PO}_{4} \rightarrow \mathrm{H}_{5}\mathrm{P}_{3}\mathrm{O}_{10} + 5\mathrm{H}_{2}\mathrm{O} \).

This approach ensures that each atom type is conserved across the reaction, highlighting the importance of precision in chemical equation balancing. Proper balancing is essential for accurately describing reactions and predicting the amounts of materials involved.