(a)
Interpretation:
The value of enthalpy change
Concept introduction:
The change in the enthalpy of a reaction when the reactant is converted into product under standard conditions is called standard enthalpy of reaction.
The expression for standard enthalpy of reaction is,
Here,
(a)
Explanation of Solution
The value of
Given:
Refer to Appendix L for the values of standard enthalpy of formation.
The standard enthalpy of formation of
The standard enthalpy of formation of
The standard enthalpy of formation of
The standard enthalpy of formation of
The reaction involved in photosynthesis is,
The
Substitute the value of
The value of
(b)
Interpretation:
The enthalpy change involved in producing one molecule of glucose by the process of photosynthesis at
Concept introduction:
The relationship between the number of moles and the number of molecules is,
Also,
(b)
Explanation of Solution
The enthalpy change involved in producing one molecule of glucose by the process of photosynthesis at
Given:
The enthalpy change involved in the production of one mole of glucose by the process of photosynthesis at
Since
The enthalpy change involved in producing one molecule of glucose by the process of photosynthesis is
(c)
Interpretation:
The energy of a photon of light having a wavelength
Concept introduction:
The energy of one photon
Here,
Value of
(c)
Explanation of Solution
The energy of a photon of light having wavelength
Given:
The wavelength of light is
The speed of light is
Planks constant is
Substitute the values in equation (2).
The energy of a photon of light having wavelength
(d)
Interpretation:
The absorption of one photon at
Concept introduction: If the energy of one photon is greater than the energy required for the production of one mole of substance then single photon absorption is sufficient for the reaction to proceed else multiple photons must be absorbed.
(d)
Explanation of Solution
The energy of one photon calculated in part(c) is
Therefore multiple photons must be absorbed for the production of one molecule of glucose by photosynthesis reaction.
Want to see more full solutions like this?
Chapter 24 Solutions
Chemistry & Chemical Reactivity
- The thermochemical equation for the burning of methane, the main component of natural gas, is CH4(g)+2O2(g)CO2(g)+2H2O(l)H=890kJ (a) Is this reaction endothermic or exothermic? (b) What quantities of reactants and products are assumed if H = 890 kJ? (c) What is the enthalpy change when 1.00 g methane burns in an excess of oxygen?arrow_forwardThe enthalpy change for the following reaction is 393.5 kJ. C(s,graphite)+O2(g)CO2(g) (a) Is energy released from or absorbed by the system in this reaction? (b) What quantities of reactants and products are assumed? (c) Predict the enthalpy change observed when 3.00 g carbon burns in an excess of oxygen.arrow_forwardWhen lightning strikes, the energy can force atmospheric nitrogen and oxygen to react to make NO: N2(g)+O2(g)2NO(g)H=+181.8kJ (a) Is this reaction endothermic or exothermic? (b) What quantities of reactants and products are assumed if H = +181.8 kJ? (c) What is the enthalpy change when 3.50 g nitrogen is reacted with excess O2(g)?arrow_forward
- Although the gas used in an oxyacetylene torch (Figure 5.7) is essentially pure acetylene, the heat produced by combustion of one mole of acetylene in such a torch is likely not equal to the enthalpy of combustion of acetylene listed in Table 5.2. Considering the conditions for which the tabulated data are reported, suggest an explanation.arrow_forwardn Fig. 10.1, what kind of energy does ball A possess initially when at rest at the top of the hill? What kind of energies are involved as ball A moves down the hill? What kind of energy does ball A possess when it reaches the bottom of the hill and stops moving after hitting ball B? Where did the energy gained by ball B, allowing it to move up the hill, come from?arrow_forwardThe enthalpy change when 1 mol methane (CH4) is burned is 890 kJ. It takes 44.0 kJ to vaporize 1 mol water. What mass of methane must be burned to provide the heat needed to vaporize 1.00 g water?arrow_forward
- 9.68 What are some features of petroleum that make it such an attractive fuel?arrow_forwardHow much heat is produced by combustion of 125 g of methanol under standard state conditions?arrow_forwardWhen one mol of KOH is neutralized by sulfuric acid, q=56 kJ. (This is called the heat of neutralization.) At 23.7C, 25.0 mL of 0.475 M H2SO4 is neutralized by 0.613 M KOH in a coffee-cup calorimeter. Assume that the specific heat of all solutions is 4.18J/gC, that the density of all solutions is 1.00 g/mL, and that volumes are additive. (a) How many mL of KOH is required to neutralize H2SO4? (b) What is the final temperature of the solution?arrow_forward
- When 2.50 g of methane burns in oxygen, 125 kJ of heat is produced. What is the enthalpy of combustion per mole of methane under these conditions?arrow_forwardIf nitric acid were sufficiently heated, it can be decomposed into dinitrogen pentoxide and water vapor: 2HNO3(l)N2O5(g)+H2O(g)Hrxn=+176kJ (a) Calculate the enthalpy change that accompanies the reaction of 1.00 kg HNO3 (). (b) Is heat absorbed or released during the course of the reaction?arrow_forwardOne step in the manufacturing of sulfuric acid is the conversion of SO2(g) to SO3(g). The thermochemical equation for this process is SO2(g)+12O2(g)SO3(g)H=98.9kJ The second step combines the SO3 with H2O to make H2SO4. (a) Calculate the enthalpy change that accompanies the reaction to make 1.00 kg SO3(g). (b) Is heat absorbed or released in this process?arrow_forward
- Chemistry: The Molecular ScienceChemistryISBN:9781285199047Author:John W. Moore, Conrad L. StanitskiPublisher:Cengage LearningChemistry & Chemical ReactivityChemistryISBN:9781133949640Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage LearningChemistry & Chemical ReactivityChemistryISBN:9781337399074Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage Learning
- Chemistry: Principles and PracticeChemistryISBN:9780534420123Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward MercerPublisher:Cengage LearningChemistry: Principles and ReactionsChemistryISBN:9781305079373Author:William L. Masterton, Cecile N. HurleyPublisher:Cengage LearningChemistry by OpenStax (2015-05-04)ChemistryISBN:9781938168390Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark BlaserPublisher:OpenStax