### Thermochemistry Problems#### Question 11:**Problem Statement:**A piece of metal weighing 3.20 grams is heated to 100.0°C. It is dropped into 50.0 grams of water in a calorimeter at 22.5°C. When no further change is observed, the temperature of the water and the metal rod is 26.5°C. Ignoring any heat lost or gained by the calorimeter, what is the metal and its specific heat?**Options:**a. Cu, 0.39 J g⁻¹ K⁻¹ b. Hg, 0.14 J g⁻¹ K⁻¹ c. Pb, 0.13 J g⁻¹ K⁻¹ d. Na, 1.2 J g⁻¹ K⁻¹ e. Li, 3.6 J g⁻¹ K⁻¹ **Letter answer to question #11: _______**#### Question 12:**Problem Statement:**Calculate the amount of heat needed to change 45.0 grams of ice at -25.0°C to steam at 250.0°C. (For water, ΔH_fus = 333 J/g; ΔH_vap = 2260 J/g; Specific Heat (ice) = 2.10 J g⁻¹ K⁻¹; Specific Heat (steam) = 2.00 J g⁻¹ K⁻¹)**Options:**a. 14.7 kJ b. 33.7 kJ c. 116 kJ d. 151 kJ e. 175 kJ **Letter answer to question #12: _______**#### Explanation of Concepts:**Calorimetry:**Calorimetry is a branch of thermochemistry that deals with measuring the heat evolved or absorbed during a chemical reaction, physical change, or heat capacity. The basic process involves measuring the temperature change of a substance when subjected to heating or cooling. **Phase Change Calculations:**1. To calculate the heat needed to change ice at a specific temperature to steam, one must account for the energy required for each of the following steps: - Heating the ice to its melting point (0°C) - Melting the ice to water - Heating the water to its boiling point (100°C)

11) Mass of the piece of metal = 3.20 grams Temperature= 100o CMass of water in calorimeter = 50…

11. A piece of metal weighing 3.20 grams is heated to 100. °C. It is dropped into 50.0 grams of water in a calorimeter at 22.5 °C. When no further change is observed, the temperature of the water and the metal rod is 26.5 °C. Ignoring any heat lost or gained by the calorimeter, what is the metal and its specific heat? a. Cu, 0.39 J g-1 K-1 b. Hg, 0.14 J g-¹ K-¹ c. Pb, 0.13 Jg¹ K-¹ d. Na, 1.2 Jg-¹ K-¹ e. Li, 3.6 Jg-¹ K-1 Letter answer to question #11:

11. A piece of metal weighing 3.20 grams is heated to 100. °C. It is dropped into 50.0 grams of water in a calorimeter at 22.5 °C. When no further change is observed, the temperature of the water and the metal rod is 26.5 °C. Ignoring any heat lost or gained by the calorimeter, what is the metal and its specific heat? a. Cu, 0.39 J g-1 K-1 b. Hg, 0.14 J g-¹ K-¹ c. Pb, 0.13 Jg¹ K-¹ d. Na, 1.2 Jg-¹ K-¹ e. Li, 3.6 Jg-¹ K-1 Letter answer to question #11:

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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