What information does the chemical equation 2C4H10 + 13O2 → 8CO2 + 10H2O provide?

• A. It indicates the speed at which the reaction occurs.
• B. It shows the relative number of molecules or moles of reactants and products involved in the reaction.
• C. It describes the physical states of all substances involved.
• D. It provides the energy change associated with the reaction.

Answer: (B)

Verified step by step guidance

1. Understand that a chemical equation represents a chemical reaction by showing the reactants on the left side and the products on the right side, separated by an arrow indicating the direction of the reaction.
2. Recognize that the coefficients in front of each chemical formula (such as 2 in front of C4H10 and 13 in front of O2) indicate the relative number of molecules or moles of each substance involved in the reaction.
3. Note that the equation 2C4H10 + 13O2 → 8CO2 + 10H2O tells us how many molecules or moles of butane (C4H10) react with oxygen (O2) to produce carbon dioxide (CO2) and water (H2O).
4. Understand that this balanced equation does not provide information about the speed (rate) of the reaction, the physical states of the substances, or the energy changes (enthalpy) involved.
5. Conclude that the primary information conveyed by the chemical equation is the relative quantities of reactants and products, which is essential for stoichiometric calculations.