뒤로
- Find ∆H° in kilojoules for the reaciton of nitric oxide with oxygen, 2 NO(g) + O2(g) → N2O4(g), given the following data: N2O4(g) → 2 NO2(g) ∆H° = 55.3 kJ NO(g) + 1/2 O2(g) → NO2(g) ∆H° = -58.1 kJ
문제 96
- Set up a Hess's law cycle, and use the following information to calculate ΔH°f for aqueous nitiric acid, HNO3(aq). You will need to use fractional coefficients for some equations. 3 NO2(g) + H2O(l) → 2 HNO3(aq) + NO(g) ΔH° = -137.3 kJ 2 NO(g) + O2(g) → 2 NO2(g) ΔH° = -116.2 kJ 4 NH3(g) + 5 O2(g) → 4 NO (g) + 6 H2O(l) ΔH° = -1165.2 kJ NH3(g) ΔH°f = -46.1 kJ/mol H2O(l) ΔH°f = -285.8 kJ/mol
문제 97
- What is a compound's standard heat of formation?
문제 98
- How is the standard state of an element defined? Why do elements always have ∆H°f = 0?
문제 99
- What phase of matter is associated with the standard states of the following elements and compounds? (a) Cl2 (b) Hg (c) CO2 (d) Ga
문제 100
- What is the phase of the standard states of the following ele- ments and compounds? (a) NH3 (b) Fe (c) N2 (d) Br2
문제 101
문제 102a
Write balanced equations for the formation of the following compounds from their elements. (a) Iron(III) oxide
문제 102b
Write balanced equations for the formation of the following compounds from their elements. (b) Sucrose (table sugar, C12H22O11)
문제 103a
Write balanced equations for the formation of the following compounds from their elements. (a) Ethanol (C2H6O)
문제 103b
Write balanced equations for the formation of the following compounds from their elements. (b) Sodium sulfate
문제 103c
Write balanced equations for the formation of the following compounds from their elements. (c) Dichloromethane (a liquid, CH2Cl2)
- Sulfuric acid (H2SO4), the most widely produced chemical in the world, is amde yb a two-step oxidaiton of sulfur to sulfur trioxide, SO3, followed by reaciton with water. Calculate ΔH°f for SO3 in kJ/mol, given the following data: S(s) + O2(g) → SO2(g) ΔH° = -296.8 kJ SO2(g) + 1/2 O2(g) → SO3(g) ΔH° = -98.9 kJ
문제 104
- Calculate ∆H°f in kJ/mol for benzene, C6H6, from the following data: 2 C6H6(l) + 15 O2(g) → 12 CO2(g) + 6 H2O(l) ∆H°=-6534 kJ ∆H°f (CO2) = -393.5 kJ/mol ∆H°f(H2O) = -285.8 kJ/mol
문제 105
- The standard enthalpy change for the reaciton of SO3(g) with H2O(l) to yield H2SO4(aq) is ΔH° = -227.8 kJ. Use the information in Problem 9.104 to calculate ΔH°f for H2SO4(aq) in kJ/mol. [For H2O(l), ΔH°f = -285.88 kJ/mol.]
문제 106
- Acetic acid (CH3CO2H), whose aqueous solutions are known as vinegar, is prepared by reaction of ethyl alcohol (CH3CH2OH) with oxygen: CH3CH2OH(l) + O2(g) → CH3CO2H(l) + H2O(l) Use the following data to calculate ∆H° in kilojoules for the reaction: ∆H°f [CH3CH2OH(l)] = -277.7 kJ/mol ∆H°f [CH3CO2H(l)] = -484.5 kJ/mol ∆H°f [H2O(l)] = -285.8 kJ/mol
문제 107
- Styrene (C8H8), the precursor of polystyrene polymers, has a standard heat of combustion of -4395 kJ/mol. Write a balanced equation for the combustion reaction, and calculate ΔH°f for styrene in kJ/mol. ΔH°f [CO2(g)] = -393.5 kJ/mol; ΔH°f [H2O(l)] = -285.8 kJ/mol
문제 108
- Methyl tert-butyl ether (MTBE), C5H12O, a gasoline additive used to boost octane ratings, has ΔH°f = -313.6 kJ/mol. Write a balanced equaiton for its combustion reaciton, and calcualte its standard heat of combustion in kilojoules
문제 109
- Methyl tert-butyl ether (MTBE) is prepared by reaciton of methanol (l) (ΔH°f = -239.2 kJ/mol) with 2-methyl-propene (g), according to the requation Calculate ΔH°f in kJ/mol for 2-methylpropene
문제 110
- Answer the following questions. (e) A gallon of ice cream contains exactly 32 servings, and each serving has 165 Calories, of which 30.0% are derived from fat. How many Calories derived from fat would you consume if you ate one half of a gallon of ice cream?
문제 111
- Given the standard heats of formation shown in Appendix B, what is ΔH° in kilojoules for the reaciton CaCO3(s) → CaO(s) + CO2(g)?
문제 112
- Given the standard heats of formation shown in Appendix B, what is ΔH° in kilojoules for the reaciton 3 N2O4(g) + 2 H2O(l) → 4 HNO3(aq) + 2 NO(g)
문제 113
- Calcualte ΔH° in kilojoules for the synthesis of lime (CaO) from limestone (CaCO3), the key step in the manufacture of cement. CaCO3(s) → CaO(s) + CO2(g) ΔH°f [CaCO3(s)] = -1207.6 kJ/mol ΔH°f [CaO(s)] = -634.9 kJ/mol ΔH°f [CO2(g)] = -393.5 kJ/mol
문제 114
- Use the information in Table 9.2 to calculate ΔH° in kilojoules for the photosynthesis of glucose (C6H12O6) and O2 from CO2 and liquid H2O, a reaciton carried out by all green plants
문제 115
문제 116a
Use the data in Appendix B to find standard enthalpies of reaction in kilojoules for the following processes: (a) C(s) + CO2(g) → 2 CO(g)
문제 116b
Use the data in Appendix B to find standard enthalpies of reaction in kilojoules for the following processes: (b) 2 H2O2 (aq) → 2 H2O (l) + O2(g)
문제 116c
Use the data in Appendix B to find standard enthalpies of reaction in kilojoules for the following processes: (c) Fe2O3 (s) + 3 CO (g) → Fe(s) + 3 CO2(g)
- Isooctane, C8H18, is the component of gasoline from which the term octane rating derives (b) The standard molar heat of combustion of isooctane (l) is -5461 kJ/mol. Calculate ΔH°f for isooctane(l)
문제 117
문제 117a
Isooctane, C8H18, is the component of gasoline from which the term octane rating derives. (a) Write a balanced equation for the combustion of isooctane(l) with O2 to yield CO2(g) and H2O(l)
문제 122
What does entropy measure?
- What are the two terms that make up the free-energy change for a reaction, ΔG, and which of the two is usually more important?
문제 123