Sodium carbonate, Na2CO3, can be prepared by heating sodium hydrogen carbonate, NaHCO3.
Estimate the temperature at which NaHCO3 decomposes to products at 1 atm. See Appendix C for data.
Want to see the full answer?
Check out a sample textbook solutionChapter 18 Solutions
OWLv2 for Ebbing/Gammon's General Chemistry, 11th Edition, [Instant Access], 1 term (6 months)
- Silver carbonate, Ag2CO3, is a light yellow compound that decomposes when heated to give silver oxide and carbon dioxide: Ag2CO3(s)Ag2O(s)+CO2(g) A researcher measured the partial pressure of carbon dioxide over a sample of silver carbonate at 220C and found that it was 1.37 atm. Calculate the partial pressure of carbon dioxide at 25C. The standard enthalpies of formation of silver carbonate and silver oxide at 25C are 505.9 kJ/mol and 31.05 kJ/mol, respectively. Make any reasonable assumptions in your calculations. State the assumptions that you make, and note why you think they are reasonable.arrow_forwardUse the appropriate tables to calculate H for (a) the reaction between copper(II) oxide and carbon monoxide to give copper metal and carbon dioxide. (b) the decomposition of one mole of methyl alcohol (CH3OH) to methane and oxygen gases.arrow_forwardCalcium carbide, CaC2, is manufactured by reducing lime with carbon at high temperature. (The carbide is used in turn to make acetylene, an industrially important organic chemical.) Is the reaction endothermic or exothermic?arrow_forward
- Oxygen was first prepared by Joseph Priestley (1733-1804) by heating HgO. Use data in Appendix L to estimate the temperature required to decompose HgO(s) into Hg() and O2(g).arrow_forwardAdenosine triphosphate, ATP, is used as a free-energy source by biological cells. (See the essay on page 624.) ATP hydrolyzes in the presence of enzymes to give ADP: ATP(aq)+H2O(l)ADP(aq)+H2PO4(aq);G=30.5kJ/molat25C Consider a hypothetical biochemical reaction of molecule A to give molecule B: A(aq)B(aq);G=+15.0kJ/molat25C Calculate the ratio [B]/[A] at 25C at equilibrium. Now consider this reaction coupled to the reaction for the hydrolysis of ATP: A(aq)+ATP(aq)+H2O(l)B(aq)+ADP(aq)+H2PO4(aq) If a cell maintains a high ratio of ATP to ADP and H2PO4 by continuously making ATP, the conversion of A to B can be made highly spontaneous. A characteristic value of this ratio is [ATP][ADP][H2PO4]=500 Calculate the ratio [B][A] in this case and compare it with the uncoupled reaction. Compared with the uncoupled reaction, how much larger is this ratio when coupled to the hydrolysis of ATP?arrow_forwardActually, the carbon in CO2(g) is thermodynamically unstable with respect to the carbon in calcium carbonate(limestone). Verify this by determining the standardGibbs free energy change for the reaction of lime,CaO(s), with CO2(g) to make CaCO3(s).arrow_forward
- Natural gas, which is mostly methane, CH4, is a resource that the United States has in abundance. In principle, ethane can be obtained from methane by the reaction 2CH4(g)C2H6(g)+H2(g) (a) Calculate G° at 25°C for the reaction. Comment on the feasibility of this reaction at 25°C. (b) Couple the reaction above with the formation of steam from the elements: H2(g)+12O2(g)H2O(g)G=228.6kJ What is the equation for the overall reaction? Comment on the feasibility of the overall reaction.arrow_forwardCalculate H when a 38-g sample of glucose, C6H12O6(s), burns in excess O2(g) to form CO2(g) and H2O() in a reaction at constant pressure and 298.15 K.arrow_forwardCobalt(II) chloride hexahydrate, CoCl26H2O, is a bright pink compound, but in the presence of very dry air it loses water vapor to the air to produce the light blue anhydrous salt CoCl2. Calculate the standard free-energy change for the reaction at 25C: CoCl26H2O(s)CoCl2(s)+6H2O(g) Here are some thermodynamic data at 25C: What is the partial pressure of water vapor in equilibrium with the anhydrous salt and the hexahydrate at 25C? (Give the value in mmHg.) What is the relative humidity of air that has this partial pressure of water? The relative humidity of a sample of air is Relativehumidity=partialpressureofH2O(g)inairvaporpressureofwater100 What do you expect to happen to the equilibrium partial pressure over the hexahydrate as the temperature is raised? Explain.arrow_forward
- The formation of aluminum oxide from its elements is highly exothermic. If 2.70 g Al metal is burned in pure O2 to give A12O3, calculate how much thermal energy is evolved in the process (at constant pressure).arrow_forwardWrite a chemical equation for each process and classify each as reactant-favored or product-favored. (a) A puddle of water evaporates on a summer day. (b) Silicon dioxide (sand) decomposes to the elements Silicon and oxygen. (c) Paper, which is mainly cellulose (C6H10O5)n, bums at a temperature of 451 F. (d) A pinch of sugar dissolves in water at room temperature.arrow_forwardThe equilibrium constant for a certain reaction increases by a factor of 6.67 when the temperature is increased from 300.0 K to 350.0 K. Calculate the standard change in enthalpy (H) for this reaction (assuming H is temperature-independent).arrow_forward
- Chemistry & Chemical ReactivityChemistryISBN:9781337399074Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage LearningChemistry by OpenStax (2015-05-04)ChemistryISBN:9781938168390Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark BlaserPublisher:OpenStaxGeneral Chemistry - Standalone book (MindTap Cour...ChemistryISBN:9781305580343Author:Steven D. Gammon, Ebbing, Darrell Ebbing, Steven D., Darrell; Gammon, Darrell Ebbing; Steven D. Gammon, Darrell D.; Gammon, Ebbing; Steven D. Gammon; DarrellPublisher:Cengage Learning
- ChemistryChemistryISBN:9781305957404Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCostePublisher:Cengage LearningChemistry: An Atoms First ApproachChemistryISBN:9781305079243Author:Steven S. Zumdahl, Susan A. ZumdahlPublisher:Cengage Learning