An average human produces about 10 MJ of heat each day through metabolic activity. IF a human body were an isolated system of mass 65 kg with the heat capacity of water, what temperature would the body experience? Human bodies are actually open systems, and the main mechanism of heat loss is through evaporative cooling. What mass of water should be evaporated each day to maintain constant temperature? Cp,m (water) = 75.29 J/K-mol qp = CpAT = nCp,mAT AHevaporation = 44.016 x 10³J/mol

An average human produces about 10 MJ of heat each day through metabolic activity. IF a human body were an isolated system of mass 65 kg with the heat capacity of water, what temperature would the body experience? Human bodies are actually open systems, and the main mechanism of heat loss is through evaporative cooling. What mass of water should be evaporated each day to maintain constant temperature? Cp,m (water) = 75.29 J/K-mol qp = CpAT = nCp,mAT AHevaporation = 44.016 x 10³J/mol

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...

See similar textbooks

Similar questions

A simple method for the laboratory preparation of hydrogen involves reaction of zinc with hydrochloric acid; Zn(s) + 2 HCl(aq) → ZnCl 2(aq) + H 2(g) ΔH = -152.5 kJHow much heat in kilojoules is evolved if a total of 925.1 mL of H 2 was collected over water at 22.00 ° C and an atmospheric pressure of 291.7 mm Hg. The partial pressure of water at this temperature is 19.83 mm Hg? Assume heat evolved is directly proportional to the moles produced.
A 50.0 mL sample of a 1.00 MM solution of CuSO4CuSO4 is mixed with 50.0 mL of 2.00 MM KOHKOH in a calorimeter. The temperature of both solutions was 24.6 oCoC before mixing and 32.8 oCoC after mixing. The heat capacity of the calorimeter is 12.1 J/K. From these data, calculate ΔHΔH for the process: CuSO4(1M)+2KOH(2M)→Cu(OH)2(s)+K2SO4(0.5M)CuSO4(1M)+2KOH(2M)→Cu(OH)2(s)+K2SO4(0.5M) Assume that the specific heat and density of the solution after mixing are the same as those of pure water and that the volumes are additive.
If a 136.51 g Al rod (c = 0.900 J/g°C) is at 100.0°C and placed into 250.0 g of water at 21.8°C, what is the temperature of the system (rod + water) at equilibrium assuming %3D no losses to the surroundings? Assume the specific heat of water to be 4.18 J/g°C. (A 46°C 30°C c) 206°C 18°C
Potassium nitrate, KNO 3, has a molar mass of 101.1 g/mol. In a constant-pressure calorimeter, 41.8 g of KNO3 is dissolved in 277 g of water at 23.00 °C. KNO3(s) H₂O K+(aq) + NO3(aq) The temperature of the resulting solution decreases to 20.90 °C. Assume that the resulting solution has the same specific heat as • water, 4.184 J/(g · °C), and that there is negligible heat loss to the surroundings. How much heat was released by the solution? Isoln = What is the enthalpy of the reaction? AH rxn = KJ kJ/mol
7. An old "trick" for cooling down a hot beverage quickly is to immerse a cold spoon into the liquid. A silver spoon weighing 3.20 oz and at a temperature of 20°C is placed in a cup of hot coffee (8.00 oz) at 70°C. What will be the resulting liquid temperature? Assume that specific heat of coffee is 4.18 J g-1 °C-1 and that of silver is 0.234 J g-¹ °C-1. Comment on the effectiveness of this method of cooling a hot drink. 1 g = 0.0352 oz
Consider an unknown metal X with a mass of 67.5 g at an initial temperature of 76.1 °C. The metal is placed in 88.7 g of water initially at 20.5 °C in an insulated container. The final equilibrium temperature of the system is 32.1 °C. Calculate the specific heat (J/(g·°C)) of the metal X. Use Cs = 4.18 J/(g·°C) for the specific heat of water. Assume that the only energy exchange that occurs is between the metal and the water.
Phthalates used as plasticizers in rubber and plastic products are believed to act as hormone mimics in humans. The value of ΔHcomb for dimethylphthalate (C10H10O4) is –4685 kJ/mol. Assume 0.910 g of dimethylphthalate is combusted in a calorimeter whose heat capacity (Ccalorimeter) is 7.40 kJ/°C at 22.0 °C. What is the final temperature of the calorimeter? °C
A quantity of 2.00×102 mL of 0.786 M HCl is mixed with 2.00×102 mL of 0.393 M Ba(OH)2 in a constant-pressure calorimeter of negligible heat capacity. The initial temperature of the HCl and Ba(OH)2 solutions is the same at 20.76°C. For the process below, the heat of neutralization is −56.2 kJ/mol. What is the final temperature of the mixed solutions? H+(aq) + OH−(aq)→H2O(l) _____°C
Phthalates used as plasticizers in rubber and plastic products are believed to act as hormone mimics in humans. The value of ΔHcomb for dimethylphthalate (C10H10O4) is –4685 kJ/mol. Assume 1.16 g of dimethylphthalate is combusted in a calorimeter whose heat capacity (Ccalorimeter) is 7.85 kJ/°C at 20.0 °C. What is the final temperature of the calorimeter?
A student followed the procedure in this experiment , using 29.5 mL of 2.41 molar HCl and 31.5 mL of 2.41 molar NaOH , with both solutions having an initial temperature of 21.9 °C. After mixing , a maximum temperature of 31.0 °C is measured . The final mass of the mixture was found to be 62.201 grams . For this problem , assume the specific heat of the solution is 4.18 J/g °C. What is the heat transferred by this reaction, in Joules?
Calculate the heat required to raise the temperature of a 50.0 g of water from 25.0 °C to 39.0 °C. (The specific heat capacity of water is 4.184 J·g–1·°C–1). A) 2.93 kJ B) 4.18 kJ C) 5.23 kJ D) 8.16 kJ 0.163 kJ
Consider a balloon filled with 2115 L of helium at 1.00 atm pressure and 45.5°C. The temperature of the balloon is decreased to 26.3°C with the pressure remaining at 1.00 atm. What is ∆E (in kJ) for this change? (Assume ideal conditions. The molar heat capacity for He at constant pressure, Cp, is 20.8 J/°C･mol.)