What is the half-life for the first-order decay of phosphorus-32?
Trending nowThis is a popular solution!
Chapter 12 Solutions
Chemistry by OpenStax (2015-05-04)
Additional Science Textbook Solutions
College Physics
Chemistry: Structure and Properties
Chemistry: Structure and Properties (2nd Edition)
Introductory Chemistry (5th Edition) (Standalone Book)
Organic Chemistry (9th Edition)
Essential Organic Chemistry (3rd 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_forwardExplain why half-lives are not normally used to describe reactions other than first order.arrow_forwardBoth technetium-99 and thallium-201 are used to image heart muscle in patients with suspected heart problems. The half-lives are 6 h and 73 h, respectively. What percent of the radioactivity would remain for each of the isotopes after 2 days (48 h)?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) 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_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) 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_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_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_forwardIn the presence of excess thiocyanate ion, SCN, the following reaction is first order in iron(III) ion, Fe3+; the rate constant is 1.27/s. Fe3+(aq)+SCN(aq)Fe(SCN)2+(aq) What is the half-life in seconds? How many seconds would be required for the initial concentration of Fe3+ to decrease to each of the following values: 25.0% left, 12.5% left, 6.25% left, 3.125% left? What is the relationship between these times and the half-life?arrow_forward
- The decomposition of many substances on the surface of a heterogeneous catalyst shows the following behavior: How do you account for the rate law changing from first order to zero order in the concentration of reactant?arrow_forwardLabel the elementary processes for the reaction between H2 and O2 see section 20.7 as initiation, propagation, branching, or termination reactions.arrow_forwardCompare the functions of homogeneous and heterogeneous catalysts.arrow_forward
- Chemistry by OpenStax (2015-05-04)ChemistryISBN:9781938168390Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark BlaserPublisher:OpenStaxChemistry: 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 Learning
- Chemistry & Chemical ReactivityChemistryISBN:9781133949640Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage LearningChemistry: Principles and ReactionsChemistryISBN:9781305079373Author:William L. Masterton, Cecile N. HurleyPublisher:Cengage LearningChemistry for Engineering StudentsChemistryISBN:9781337398909Author:Lawrence S. Brown, Tom HolmePublisher:Cengage Learning