Chapter 9, Problem 35A

Interpretation Introduction

Interpretation:The most suitable statement to explain the reason of not adding masses of reactant to determine the mass of product during the chemical reaction needs to be identified.

Concept Introduction:A chemical reaction involves the conversion of reactant to product by breaking and making of chemical bonds.

A balance chemical reaction equation interprets the balance moles of each molecule in the chemical reaction.

Answer to Problem 35A

Correct answer: Option (e) is correct.

Explanation of Solution

Reason for correct option:In the chemical reaction, the mole ratio of reactant and product must be used. According to the Law of mass conservation, the mass should remain same before and after the reaction. Here, the mass represents the molar mass not the actual mass given in the laboratory.

Since the molar mass is related moles and it is specific for each molecule therefore it should be used to calculate total mass of the product formed.

Conclusion

Reasons for incorrect options: The given mass of reactant can vary with experiment therefore masses of reactant cannot be used as standard mass to calculate total mass of product. The coefficient of reactant indicates the moles of reactant molecules so they cannot multiply with masses of reactant molecules.