1. In the olden days, US minted pennies were pure copper, but copper got so expensive that a pure copper penny was worth more than 1 cent. Modern pennies are composed of zinc and coated with student determines the mass of a penny to be 2.482 g. After making several scratches in a penny, the student puts the penny into hydrochloric acid, where the zinc (but not the copper) reacts with hydrochloric acid via a single replacement reaction. The hydrogen is collected at 25°C over water. The collected gas occupies 0.899L at a total pressure of 791 mm Hg. copper. A. Calculate the moles of hydrogen produced in the reaction. (Hint: Use the Table 1. to determine the vapor pressure of water and assume that all of the zinc in the penny dissolves.) B. Write a balanced chemical reaction for zinc and hydrochloric acid. C. Use stoichiometry to calculate the mass of zinc in the penny. D.Determine the percent zinc (by mass) in the penny.

1. In the olden days, US minted pennies were pure copper, but copper got so expensive that a pure copper penny was worth more than 1 cent. Modern pennies are composed of zinc and coated with student determines the mass of a penny to be 2.482 g. After making several scratches in a penny, the student puts the penny into hydrochloric acid, where the zinc (but not the copper) reacts with hydrochloric acid via a single replacement reaction. The hydrogen is collected at 25°C over water. The collected gas occupies 0.899L at a total pressure of 791 mm Hg. copper. A. Calculate the moles of hydrogen produced in the reaction. (Hint: Use the Table 1. to determine the vapor pressure of water and assume that all of the zinc in the penny dissolves.) B. Write a balanced chemical reaction for zinc and hydrochloric acid. C. Use stoichiometry to calculate the mass of zinc in the penny. D.Determine the percent zinc (by mass) in the penny.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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