In the laboratory a "coffee cup" calorimeter, or constant pressure calorimeter, is frequently used to determine the specific heat of a solid, or to Thermometer measure the energy of a solution phase reaction. Stirring rod A student heats 66.79 grams of zinc to 98.02 °C and then drops it into a cup containing 80.33 grams of water at 23.98 °C. She measures the final temperature to be 29.09 °C. The heat capacity of the calorimeter (sometimes referred to as the calorimeter constant) was determined in a separate experiment be 1.74 J/°C. Water Assuming that no heat is lost to the surroundings calculate the specific heat of zinc. Metal sample Specific Heat (Zn) = J/g°C. Thomonrc

In the laboratory a "coffee cup" calorimeter, or constant pressure calorimeter, is frequently used to determine the specific heat of a solid, or to Thermometer measure the energy of a solution phase reaction. Stirring rod A student heats 66.79 grams of zinc to 98.02 °C and then drops it into a cup containing 80.33 grams of water at 23.98 °C. She measures the final temperature to be 29.09 °C. The heat capacity of the calorimeter (sometimes referred to as the calorimeter constant) was determined in a separate experiment be 1.74 J/°C. Water Assuming that no heat is lost to the surroundings calculate the specific heat of zinc. Metal sample Specific Heat (Zn) = J/g°C. Thomonrc

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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A 70.0-g piece of metal at 80.0 °C is placed in 100 g of water at 22.0 °C contained in a calorimeter like that shown. The metal and water come to the same temperature at 24.6 °C. How much heat did the metal give up to the water? What is the specific heat of the metal?
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A student is asked to identify an unknown piece of metal. The metal has a mass of 12.34 g. It is placed in a boiling water bath and brought up to 99.98 oC. A coffee-cup calorimeter is set up with 103.25 mL of water (density = 1.00 g/mL and specific heat = 4.184 J/g.oC) at a room temperature of 21.30 oC. The metal is removed from the boiling water and placed in the calorimeter. A final temperature is recorded as 22.32 oC. Find the specific heatcapacity of the unknown metal. (Assume there is no heat loss)
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3. A 74.5 g piece of metal at 86.0°C is placed in 133 g of water at 21.0°C contained in a calorimeter. The metal and water come to the same temperature at 24.2°C. How much heat (in J) did the metal give up to the water? (Assume the specific heat of water is 4.18 J/g·°C across the temperature range.) J What is the specific heat (in J/g·°C) of the metal? J/g·°C 4. A 0.528 g sample of KCl is added to 51.7 g of water in a calorimeter. If the temperature decreases by 1.07°C, what is the approximate amount of heat (in J) involved in the dissolution of the KCl, assuming the heat capacity of the resulting solution is 4.18 J/g°C? J Is the reaction exothermic or endothermic? exothermicendothermic 5. When 2.56 g of methane burns in oxygen, 128 kJ of heat is produced. What is the enthalpy of combustion (in kJ) per mole of methane under these conditions? kJ/mol methane 6. Joseph Priestly prepared oxygen in 1774 by heating red mercury(II) oxide with sunlight focused through a lens. How much…
A 4.81 g sample of an unknown salt (MM = 116.82 g/mol) is dissolved in 150.00 g water in a coffee cup calorimeter. Before placing the sample in the water, the temperature of the salt and water is 23.72°C. After the salt has completely dissolved, the temperature of the solution is 28.54°C. If 3.12 × 10³ J of heat was gained by the solution, what is the total heat for the dissolution reaction of the 4.81 g of salt? How many moles of the unknown salt were used in the reaction ? _______ J?
A 42.0 g sample of water at 100.00°C was placed in an insulated cup. Then 15.4 g of zinc metal at 23.60°C was added to the water. The temperature of the water dropped to 97.52°C. What is the specific heat of zinc? Assume the specific heat is that of pure water, 4.18 J/(g⋅°C).
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