Complete the exercises below. Write a molecular formula for each compound, and indicate the oxidation state of the group 5A element in each formula: a. phosphorous acid, b. pyrophosphoric acid, c. antimony trichloride, d. magnesium arsenide, e. diphosphorus pentoxide, f. sodium phosphate.

A molecular formula represents the number and types of atoms in a molecule. It is expressed using chemical symbols and subscripts, indicating the quantity of each element present. For example, the molecular formula for water is H2O, indicating two hydrogen atoms and one oxygen atom. Understanding how to derive molecular formulas is essential for identifying compounds and their compositions.

The oxidation state, or oxidation number, of an element in a compound indicates the degree of oxidation or reduction of that element. It is a theoretical charge that an atom would have if all bonds were ionic. For group 5A elements, such as phosphorus and arsenic, the oxidation states can vary based on the compound, influencing their chemical behavior and reactivity. Recognizing oxidation states is crucial for understanding redox reactions and compound stability.

Acids are substances that can donate protons (H+) in a solution, and their molecular formulas often reflect their acidic nature. For example, phosphorous acid (H3PO3) contains hydrogen ions that contribute to its acidity. Understanding the structure and formula of different acids, including polyprotic acids like pyrophosphoric acid, is important for predicting their behavior in chemical reactions and their role in various applications.