45. A50g sample of NaCl is added to a Styrofoam cup of water, and the change in water temperature is 5.0 °C. The heat of solution of NaCl is 3.76 kJ/ mol. What is the mass (in g) of water in the Styrofoam cup? Use Hess's law to determine AH for the reaction -COg), given that Cpmphite) +04g) - - CO(g) AH = -110.54k] Cigaphite)+Ofg) CO(g) AH-393.51 k]

45. A50g sample of NaCl is added to a Styrofoam cup of water, and the change in water temperature is 5.0 °C. The heat of solution of NaCl is 3.76 kJ/ mol. What is the mass (in g) of water in the Styrofoam cup? Use Hess's law to determine AH for the reaction -COg), given that Cpmphite) +04g) - - CO(g) AH = -110.54k] Cigaphite)+Ofg) CO(g) AH-393.51 k]

Chemistry & Chemical Reactivity

10th Edition

ISBN:9781337399074

Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Publisher:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Chapter5: Principles Of Chemical Reactivity: Energy And Chemical Reactions

Section5.6: Calorimetry

Problem 5.7CYU: Assume 200. mL of 0.400 M HCl is mixed with 200. mL of 0.400 M NaOH in a coffee-cup calorimeter The...

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Assume 200. mL of 0.400 M HCl is mixed with 200. mL of 0.400 M NaOH in a coffee-cup calorimeter The temperature of the solutions before mixing was 25.10 C; after mixing and allowing the reaction to occur, the temperature is 27.78 C. What is the enthalpy change when one mole of acid is neutralized? (Assume that the densities of all solutions are 1.00 g/mL and their specific heat capacities are 4.20 J/g K.)
A sample of nickel is heated to 99.8C and placed in a coffee-cup calorimeter containing 150.0 g water at 23.5C. After the metal cools, the final temperature of metal and water mixture is 25.0C. If the specific heat capacity of nickel is 0.444 J/C g, what mass of nickel was originally heated? Assume no heat loss to the surroundings.
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The addition of 3.15 g of Ba(OH)28H2O to a solution of 1.52 g of NH4SCN in loo g of water in a calorimeter caused the temperature to fall by 3.1 C. Assuming the specific heat of the solution and products is 4.20 J/g C, calculate the approximate amount of heat absorbed by the reaction, which can be represented by the following equation: Ba(OH)28H2O(s)+2NH4SCN(aq)Ba(SCN)2(aq)+2NH3(aq)+10H2O(l)
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