Concept explainers
Evaporating sweat cools the body because evaporation is endothermic and absorbs 2.44 kJ per gram of water evaporated. Estimate the mass of water that must evaporate from the skin to cool a body by 0.50 °C, if the mass of the body is 95 kg and its heat capacity is 4.0 J/g °C. (Assume that the heat transfer is 100% efficient.)
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Chapter 3 Solutions
Introductory Chemistry, Books a la Carte Edition & Modified MasteringChemistry with Pearson eText -- ValuePack Access Card -- for Introductory Chemistry Package
Additional Science Textbook Solutions
Chemistry: A Molecular Approach (4th Edition)
Chemistry: Structure and Properties (2nd Edition)
Chemistry (7th Edition)
Chemistry: An Introduction to General, Organic, and Biological Chemistry (13th Edition)
Chemistry For Changing Times (14th Edition)
Chemistry & Chemical Reactivity
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- In the “Chemistry in Focus” segment Firewalking: Magic or Science?, it is claimed that one reason people can walk on hot coals is that human tissue is mainly composed of water. Because of this, a large amount of heat must be transferred from the coals to change the temperature of the feet significantly. How much heat must be transferred to 100.0 g of water to change its temperature by 35 °C?arrow_forwardA block of aluminum and a block of iron, both having the same mass, are removed from a freezer and placed outside on a warm day. When the same quantity of heat has flowed into each block, which block will be warmer? Assume that neither block has yet reached the outside temperature. (See Table 6.1 for the specific heats of the metals.)arrow_forwardThe initial temperature of a 344-g sample of iron is 18.2 C. If the sample absorbs 2.25 kJ of energy as heat, what is its final temperature?arrow_forward
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