Chemistry for Engineering Students
4th Edition
ISBN: 9781337398909
Author: Lawrence S. Brown, Tom Holme
Publisher: Cengage Learning
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Chapter 9, Problem 9.84PAE
9.84 Some claim it would be more logical to use heats of atomization, the energy required to convert any molecule to its separated atoms, rather than heats of formation for doing calculations with Hess's law. If you had a table of heats of atomization and calculated the combustion energy of a fuel, would you get the same answer as you would get using heats of formation? Explain your answer.
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Chemistry for Engineering Students
Ch. 9 - Explain the economic importance of conversions...Ch. 9 - • define work and beat using the standard sign...Ch. 9 - • define state functions and explain their...Ch. 9 - • state the first law of thermodynamics in words...Ch. 9 - • use calorimetric data to obtain values for E and...Ch. 9 - • define Hfo and write formation reactions for...Ch. 9 - • explain Hess’s law in your own words.Ch. 9 - • calculate H for chemical reactions from...Ch. 9 - Prob. 9.1PAECh. 9 - Prob. 9.2PAE
Ch. 9 - Prob. 9.3PAECh. 9 - Prob. 9.4PAECh. 9 - Prob. 9.5PAECh. 9 - Prob. 9.6PAECh. 9 - Define the term internal energy.Ch. 9 - How fast (in meters per second) must an iron ball...Ch. 9 - What is the kinetic energy of a single molecule of...Ch. 9 - 9.10 The kinetic energy of molecules is often used...Ch. 9 - 9.11 Analyze the units of the quantity...Ch. 9 - 9.12 How many kilojoules are equal to 3.27 L atm...Ch. 9 - Prob. 9.13PAECh. 9 - Prob. 9.14PAECh. 9 - 9.15 Carry out the following conversions of energy...Ch. 9 - 9.16 According to Figure 9.2, the total energy...Ch. 9 - 9.17 If a machine does 4.8103kJ of work after an...Ch. 9 - 9.18 Calculate (a) q when a system does 54J of...Ch. 9 - 9.19 If the algebraic sign of E is negative, in...Ch. 9 - 9.20 State the first law of thermodynamics briefly...Ch. 9 - 9.21 Which type of energy heat or work, is valued...Ch. 9 - 9.12 PV-work occurs when volume changes and...Ch. 9 - 9.23 Which system does not work: (a) E=436J ,...Ch. 9 - 9.29 In which case is heat added to the system:...Ch. 9 - Prob. 9.25PAECh. 9 - 9.26 Gas furnaces have achieved impressive...Ch. 9 - Prob. 9.27PAECh. 9 - 9.28 When an electrical appliance whose power...Ch. 9 - Prob. 9.29PAECh. 9 - 9.30 For the example of shallow water and sandy...Ch. 9 - 9.31 A metal radiator is made from 26.0 kg of...Ch. 9 - 9.32 The material typically used to heat metal...Ch. 9 - 9.33 Copper wires used to transport electrical...Ch. 9 - 9.34 A copper nail and an iron nail of the same...Ch. 9 - 9.35 A piece of titanium metal with a mass of 20.8...Ch. 9 - 9.36 Define the term calibration.Ch. 9 - 9.37 A calorimeter contained 75.0 g of water at...Ch. 9 - 9.38 The energy densities of various types of coal...Ch. 9 - 9.39 How much thermal energy is required to heat...Ch. 9 - Prob. 9.40PAECh. 9 - 9.41 Under what conditions does the enthalpy...Ch. 9 - 9.42 Why is enthalpy generally more useful than...Ch. 9 - Prob. 9.43PAECh. 9 - Prob. 9.44PAECh. 9 - 9.45 What happens to the temperature of a material...Ch. 9 - 9.46 The heat of fusion of pure silicon is 43.4...Ch. 9 - 9.47 If 14.8 kJ of heat is given off when 1.6 g of...Ch. 9 - 9.48 Calculate the energy required to convert 1.70...Ch. 9 - 9.49 Hvap=31.3 kJ/mol for acetone. If 1.40 kg of...Ch. 9 - 9.50 When a 13.0-g sample of NaOH(s) dissolves in...Ch. 9 - Prob. 9.51PAECh. 9 - 9.52 Write the formation reaction for each of the...Ch. 9 - 9.53 Using these reactions, find the standard...Ch. 9 - 9.54 The phase change between graphite and diamond...Ch. 9 - 9.55 Hydrogen gas will react with either acetylene...Ch. 9 - 9.56 Using heats of formation tabulated in...Ch. 9 - 9.57 The heat of combustion of butane is —2877...Ch. 9 - 9.58 For the reaction C2H2(g)+2H2(g)C2H6,H=136 kJ....Ch. 9 - 9.59 For the reaction N2(g)+O2(g)2NO(g),H=180.5kJ...Ch. 9 - 9.60 Nitroglycenne, C3H5(NO3)3( l ), is an...Ch. 9 - 9.61 Silane, SiH4, burns according to the...Ch. 9 - 9.62 Sulfur trioxide can be removed from the...Ch. 9 - 9.63 Reactions of hydrocarhons are often studied...Ch. 9 - Prob. 9.64PAECh. 9 - 9.65 When 0.0157 g of a compound with a heat of...Ch. 9 - Prob. 9.66PAECh. 9 - Prob. 9.67PAECh. 9 - 9.68 What are some features of petroleum that make...Ch. 9 - 9.69 How are the roles of transmission substations...Ch. 9 - 9.70 Residential electric service in the United...Ch. 9 - 9.71 In recent years, the notion of a “smart grid”...Ch. 9 - 9.72 Although it can be a nuisance when a laptop...Ch. 9 - 9.73 Without looking up any numerical data or...Ch. 9 - 9.74 Without looking up any numerical data or...Ch. 9 - 9.75 Explain why each of the following chemical...Ch. 9 - 9.76 Which of the following are state functions?...Ch. 9 - 9.77 When a reaction is exothermic, is the sum of...Ch. 9 - Prob. 9.78PAECh. 9 - Prob. 9.79PAECh. 9 - Prob. 9.80PAECh. 9 - 9.81 A substance has the following properties:...Ch. 9 - 9.82 The specific heat of gold is 0.13 J g-1 K-1...Ch. 9 - 9.83 A student performing a calorimetry experiment...Ch. 9 - 9.84 Some claim it would be more logical to use...Ch. 9 - 9.85 The figure below shows a "self-cooling"...Ch. 9 - 9.86 You make some iced tea by dropping 134 g of...Ch. 9 - 9.87 What will be the final temperature of a...Ch. 9 - Prob. 9.88PAECh. 9 - 9.89 A sample of gas is 80.0% CH4 and 20.0% C2H6...Ch. 9 - 9.90 Many engineering designs must incorporate...Ch. 9 - 9.91 You want to heat the air in your house with...Ch. 9 - Prob. 9.92PAECh. 9 - Prob. 9.93PAECh. 9 - Prob. 9.94PAECh. 9 - 9.95 How much heat is required to convert 250 g of...Ch. 9 - 9.96 Most first aid "cold packs" are based on the...Ch. 9 - 9.97 Suppose that the working fluid inside an...Ch. 9 - 9.98 Hydrogen combines with oxygen in fuel cells...Ch. 9 - 9.99 The chemical reaction...Ch. 9 - 9.100 Two baking sheets are made of different...Ch. 9 - Prob. 9.101PAECh. 9 - 9.102 A runner generates 418 kJ of energy per...Ch. 9 - 9.103 One reason why the energy density of a fuel...Ch. 9 - 9.104 An engineer is using sodium metal as a...Ch. 9 - Prob. 9.105PAECh. 9 - Prob. 9.106PAECh. 9 - Prob. 9.107PAECh. 9 - Prob. 9.108PAECh. 9 - Prob. 9.109PAECh. 9 - Prob. 9.110PAE
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- Hydrazine, N2H4, is a colorless liquid used as a rocket fuel. What is the enthalpy change for the process in which hydrazine is formed from its elements? N2(g)+2H2(g)N2H4(l) Use the following reactions and enthalpy changes: N2H4(l)+O2(g)N2(g)+2H2O(l);H=622.2kJH2(g)+12O2(g)H2O(l);H=285.8kJarrow_forwardWhich of the enthalpies of combustion in Table 5.2 the table are also standard enthalpies of formation?arrow_forwardThe first step in the preparation of lead from its ore (galena, PbS) consists of roasting the ore. PbS(s)+32O2(g)SO2(g)+PbO(s) Calculate the standard enthalpy change for this reaction, using enthalpies of formation (see Appendix C).arrow_forward
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