What do chemical formulas indicate?

What do chemical formulas indicate?

• A. A model of reaction pathways.
• B. The energy of formation.
• C. Symbolic representations of the composition of a compound, indicating the types and numbers of atoms present.
• D. The spatial arrangement of atoms in three dimensions.

Answer: (C)

Chemical formulas indicate the types and numbers of atoms in a substance, i.e., its composition. For example, H2O means each molecule contains two hydrogen atoms and one oxygen atom, while CO2 has one carbon and two oxygens. They reveal what the substance is made from, not how those atoms are connected or arranged in space. A formula doesn’t show bonding patterns or geometry, which you’d need structural formulas or 3D models to understand. It also doesn’t provide information about energy changes during formation or the steps of a reaction—that requires thermodynamic data and reaction mechanisms. So, the formula is a concise representation of composition (and it can be the empirical or molecular form), not a map of structure or energetics.

Chemical formulas indicate the types and numbers of atoms in a substance, i.e., its composition. For example, H2O means each molecule contains two hydrogen atoms and one oxygen atom, while CO2 has one carbon and two oxygens. They reveal what the substance is made from, not how those atoms are connected or arranged in space. A formula doesn’t show bonding patterns or geometry, which you’d need structural formulas or 3D models to understand. It also doesn’t provide information about energy changes during formation or the steps of a reaction—that requires thermodynamic data and reaction mechanisms. So, the formula is a concise representation of composition (and it can be the empirical or molecular form), not a map of structure or energetics.