• redpanda320
In summary, the conversation discusses the exposure of a laboratory rat to an alpha-radiation source with an activity of 11.3 mCi. The activity is converted to disintegrations per second and becquerels. The rat, with a mass of 315 grams, is exposed to the radiation for 12.3 seconds and absorbs 39% of the emitted alpha particles with an energy of 9.10X10^-13 Jeules. The absorbed dose is then calculated in millirads and grays, taking into consideration the RBE of the radiation, which is 9.5. The effective absorbed dose is also calculated in mrem and Sv. Methods for solving the problem are mentioned, including converting units and
redpanda320

## Homework Statement

A laboratory rat is exposed to an alpha-radiation source whose activity is 11.3 mCi. What is the activity of the radiation in disintegrations per second? in becquerels? The rat has a mass
of 315 grams and is exposed to the radiation for 12.3 seconds, absorbing 39% of the emitted alpha particles, each having an energy of 9.10X10^-13 Jeules. Calculate the absorbed does in millirads and grays. If the RBE of the radiation is 9.5, calculate the effective absorbed dose in mrem and Sv.
Activity of the radiation in disintegrations per second= 4.2X10^8 dis/s
Activity of the radiation in becquerels= 4.2X10^8 Bq

ln (Nt/N0)= -kt
k= 0.693/t1/2
E=mc2

## The Attempt at a Solution

I started answering the question by converting the given amount of mCi to Ci.
Then converting that amount into dis/s and then into Bq.

After that, I was not exactly sure how to approach part B. A push in the right direction would help

can anyone at least tell me a method or something for how to figure out how to calculate the absorbed dose in grays?

me out a lot.

I would like to clarify that the given information does not provide enough details to accurately solve the problem. The first step would be to determine the half-life of the alpha-radiation source, as it is needed to calculate the activity. Once the half-life is known, the activity can be calculated using the given formula k= 0.693/t1/2.

As for part B, it is important to note that the absorbed dose is a measure of energy deposited in a material and is different from the activity of the radiation. It is calculated using the formula D= E/m, where E is the energy deposited and m is the mass of the material. In this case, the energy deposited can be calculated by multiplying the number of absorbed alpha particles (39% of the emitted particles) by their individual energy (9.10X10^-13 Jeules).

To calculate the absorbed dose in millirads, the energy deposited (in Joules) needs to be converted to rads using the conversion factor 1 rad= 0.01 J/kg. Similarly, to calculate the absorbed dose in grays, the energy deposited needs to be converted to Gy using the conversion factor 1 Gy= 1 J/kg.

To calculate the effective absorbed dose in mrem and Sv, the absorbed dose needs to be multiplied by the radiation weighting factor (RBE) of 9.5. The RBE takes into account the different biological effects of different types of radiation. Finally, to convert the absorbed dose from rads to rem, and from Gy to Sv, the conversion factors 1 rem= 0.01 Sv and 1 Gy= 1 Sv need to be used.

Overall, it is important to have all the necessary information and units correct in order to accurately solve the problem. If any information is missing or incorrect, it can greatly affect the final results.

## What is nuclear chemistry?

Nuclear chemistry is the study of the physical and chemical properties of elements and compounds that contain radioactive elements. It involves the study of nuclear reactions, radioactive decay, and the production and use of radioactive materials.

Radioactive decay is the process by which an unstable atomic nucleus loses energy by emitting radiation. This process can result in the transformation of one element into another, with the emission of alpha, beta, or gamma particles.

## What is the half-life of a radioactive element?

The half-life of a radioactive element is the time it takes for half of the atoms in a sample of that element to decay into a more stable form. This is a constant value for a specific isotope, and it can be used to determine the age of a sample in radioactive dating.

## How is radioactive dating used in archaeology?

Radioactive dating is used in archaeology to determine the age of artifacts and fossils. By measuring the amount of radioactive isotopes present in a sample and comparing it to the known half-life of that isotope, scientists can calculate the age of the sample.

## What are some applications of nuclear chemistry?

Nuclear chemistry has many practical applications, including the production of energy in nuclear power plants, the medical use of radioactive isotopes in diagnostic imaging and cancer treatment, and the use of radiation in industrial processes such as food preservation and sterilization.

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