Ch.22 - Chemistry of the Nonmetals
Chapter 22, Problem 82
Complete the exercises below. What is the anhydride for each of the following acids: a. H₂SO₄, b. HClO₃, c. HNO₂, d. H₂CO₃, e. H₃PO₄?

1
Step 1: Understand the concept of anhydrides. An anhydride is a compound that can form an acid when combined with water. For non-metal oxides, the anhydride is typically the oxide form of the acid without the water molecules.
Step 2: Identify the general formula for the acid and its corresponding anhydride. For an acid with the formula HₓAₒ, the anhydride is typically AₒOₓ₋₁. This involves removing water (H₂O) from the acid.
Step 3: For each acid, determine the anhydride by removing the appropriate number of water molecules. For example, for H₂SO₄, remove one H₂O to get SO₃.
Step 4: Apply this process to each acid: a. H₂SO₄ becomes SO₃, b. HClO₃ becomes Cl₂O₅, c. HNO₂ becomes N₂O₃, d. H₂CO₃ becomes CO₂, e. H₃PO₄ becomes P₂O₅.
Step 5: Verify the chemical formulas of the anhydrides by ensuring that the removal of water from the acid results in a balanced chemical equation. This ensures the correct stoichiometry and oxidation states are maintained.
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Acid-Base Chemistry
Acid-base chemistry involves the study of acids, bases, and their reactions. Acids are substances that donate protons (H⁺ ions), while bases accept protons. Understanding the properties of acids and bases is crucial for identifying their corresponding anhydrides, which are formed by the removal of water from the acid.
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Anhydrides
Anhydrides are compounds formed by the removal of water from an acid. For example, the anhydride of sulfuric acid (H₂SO₄) is sulfur trioxide (SO₃). Recognizing the relationship between acids and their anhydrides is essential for solving the given problem, as it requires knowledge of how to derive anhydrides from specific acids.
Chemical Nomenclature
Chemical nomenclature is the system of naming chemical compounds. It is important to understand the naming conventions for acids and their anhydrides, as this knowledge helps in identifying the correct anhydride for each acid listed in the question. Familiarity with common acids and their corresponding anhydrides is key to accurately answering the exercise.
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Related Practice