Skip to main content
Ch.21 - Nuclear Chemistry
Brown - Chemistry: The Central Science 14th Edition
Brown14th EditionChemistry: The Central ScienceISBN: 9780134414232Non è quello che usi tu?Cambia libro di testo
Tutti i libri di testoBrown 14th EditionCh.21 - Nuclear ChemistryProblema 69b
Capitolo 21, Problema 69b

A laboratory rat is exposed to an alpha-radiation source whose activity is 14.3 mCi. (b) The rat has a mass of 385 g and is exposed to the radiation for 14.0 s, absorbing 35% of the emitted alpha particles, each having an energy of 9.12 * 10-13 J. Calculate the absorbed dose in millirads and grays.

Guida verificata passo dopo passo
1
Convert the activity from millicuries (mCi) to disintegrations per second (becquerels, Bq) using the conversion factor: 1 mCi = 3.7 x 10^7 Bq.
Calculate the total number of disintegrations during the exposure time by multiplying the activity in Bq by the exposure time in seconds.
Determine the total energy absorbed by the rat by multiplying the total number of disintegrations by the energy per alpha particle and the absorption percentage (35%).
Calculate the absorbed dose in grays (Gy) by dividing the total energy absorbed (in joules) by the mass of the rat (in kilograms).
Convert the absorbed dose from grays to millirads using the conversion factor: 1 Gy = 100,000 millirads.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
10m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Radioactivity and Alpha Particles

Radioactivity is the process by which unstable atomic nuclei lose energy by emitting radiation. Alpha particles are a type of ionizing radiation consisting of two protons and two neutrons, emitted from the nucleus of an atom. They have a relatively low penetration power but can cause significant damage to biological tissues if absorbed.
Video consigliato:
Percorso guidato
02:48
Characteristics of Alpha Particles

Absorbed Dose

The absorbed dose is a measure of the energy deposited by ionizing radiation in a given mass of tissue, expressed in grays (Gy) or rads. One gray is defined as the absorption of one joule of radiation energy per kilogram of matter. The absorbed dose is crucial for assessing the potential biological effects of radiation exposure.
Video consigliato:
Percorso guidato
02:30
Endothermic & Exothermic Reactions

Conversion between Units

In radiation measurement, it is often necessary to convert between different units, such as millirads and grays. One rad is equivalent to 0.01 gray, and one millirad is one-thousandth of a rad. Understanding these conversions is essential for accurately reporting and interpreting radiation doses in various contexts.
Video consigliato:
Percorso guidato
01:56
Conversion Factors
Pratica correlata
Domanda del libro di testo

A laboratory rat is exposed to an alpha-radiation source whose activity is 14.3 mCi. (a) What is the activity of the radiation in disintegrations per second? In becquerels?

512
views
Domanda del libro di testo

The table to the right gives the number of protons (p) and neutrons (n) for four isotopes. (a) Write the symbol for each of the isotopes.

274
views
Domanda del libro di testo

Which are classified as ionizing radiation: X rays, alpha particles, microwaves from a cell phone, and gamma rays?

864
views
Domanda del libro di testo

Radon-222 decays to a stable nucleus by a series of three alpha emissions and two beta emissions. What is the stable nucleus that is formed?

1435
views