What is the half-life for the first-order decay of carbon-14?
Want to see the full answer?
Check out a sample textbook solutionChapter 17 Solutions
Chemistry Atoms First2e
Additional Science Textbook Solutions
College Physics
Organic Chemistry
General Chemistry: Principles and Modern Applications (11th Edition)
Chemistry: A Molecular Approach (4th Edition)
Inorganic Chemistry
Chemistry: The Central Science (14th Edition)
- Iodine-131 is used to treat tumors in the thyroid. Its decomposition is first-order with a half-life of 8.1 days. If a patient is given a sample containing 5.00 mg of I-131, how long will it take for 32% of the isotope to remain in her system?arrow_forwardSucrose, a sugar, decomposes in acid solution to give glucose and fructose. The reaction is first-order in sucrose, and the rate constant at 25 C is k = 0.21 h1. If the initial concentration of sucrose is 0.010 mol/L, what is its concentration after 5.0 h?arrow_forwardWhen formic acid is heated, it decomposes to hydrogen and carbon dioxide in a first-order decay: HCOOH(g)CO2(g)+H2(g) The rate of reaction is monitored by measuring the total pressure in the reaction container. Time (s) Pressure (torr) 0 220 50 324 100 379 150 408 200 423 250 431 300 435 Calculate the rate constant and half-life in seconds for the reaction. At the start of the reaction (time = 0), only formic acid is present. (HINT: Find the partial pressure of formic acid using Dalton's law of partial pressure and the reaction stoichiometry to find PHCOOH at each time.)arrow_forward
- When formic acid is heated, it decomposes to hydrogen and carbon dioxide in a first-order decay. HCOOH(g) CO2(g) + H2(g) At 550 C, the half-life of formic acid is 24.5 minutes. (a) What is the rate constant, and what are its units? (b) How many seconds are needed for formic acid, initially 0.15 M, to decrease to 0.015 M?arrow_forwardExplain why half-lives are not normally used to describe reactions other than first order.arrow_forwardThe decomposition of N2O5 in CCl4 is a first-order reaction. If 2.56 mg of N2O5 is present initially and 2.50 mg is present after 4.26 minutes at 55 C, what is the value of the rate constant, k?arrow_forward
- The compound Xe(CF3)2 decomposes in a first-order reaction to elemental Xe with a half-life of 30. minutes. If you place 7.50 mg of Xe(CF3)2 in a flask, how long must you wait until only 0.25 mg of Xe(CF3)2 remains?arrow_forwardRadioactive gold-198 is used in the diagnosis of liver problems. 198Au decays in a first-order process, emitting a particle (electron). The half-life of this isotope is 2.7 days. You begin with a 5.6-mg sample of the isotope. Calculate how much gold-198 remains after 1.0 day.arrow_forwardThe catalyzed decomposition of hydrogen peroxide is first-order in [H2O2]. It was found that the concentration of H2O2 decreased from 0.24 M to 0.060 M over a period of 282 minutes. What is the half-life of H2O2? What is the rate constant for this reaction? What is the initial rate of decomposition at the beginning of this experiment (when [H2O2] = 0.24 M)?arrow_forward
- At 573 K, gaseous NO2(g) decomposes, forming NO(g) and O2(g). If a vessel containing NO2(g) has an initial concentration of 1.9 102 mol/L, how long will it take for 75% of the NO2(g) to decompose? The decomposition of NO2(g) is second-order in the reactant and the rate constant for this reaction, at 573 K, is 1.1 L/mol s.arrow_forwardThe initial rate ( [NO]/ t] of the reaction of nitrogen monoxide and oxygen NO(g) + 2O2(g) NO2(g) was measured for various initial concentrations of NO and O2 at 25 C. Determine the rate equation from these data. What is the value of the rate constant, k, and what are its units?arrow_forwardHydrogen peroxide, H2O2(aq), decomposes to H2O() and O2(g) in a reaction that is first-order in H2O2 and has a rate constant k = 1.06 103 min1 at a given temperature. (a) How long will it take for 15% of a sample of H2O2 to decompose? (b) How long will it take for 85% of the sample to decompose?arrow_forward
- Chemistry: Principles and PracticeChemistryISBN:9780534420123Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward MercerPublisher:Cengage LearningChemistry & Chemical ReactivityChemistryISBN:9781337399074Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage LearningChemistry & Chemical ReactivityChemistryISBN:9781133949640Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage Learning
- Chemistry: Principles and ReactionsChemistryISBN:9781305079373Author:William L. Masterton, Cecile N. HurleyPublisher:Cengage LearningChemistry for Engineering StudentsChemistryISBN:9781337398909Author:Lawrence S. Brown, Tom HolmePublisher:Cengage LearningChemistry: The Molecular ScienceChemistryISBN:9781285199047Author:John W. Moore, Conrad L. StanitskiPublisher:Cengage Learning