Curie

Definition

The curie (symbol Ci) is a unit of radioactivity, named after the renowned physicist and chemist Marie Curie. It is used to measure the intensity of radioactive sources and is particularly relevant in the contexts of half-life and radiometric dating.

5 Must Know Facts For Your Next Test

1. One curie is defined as the amount of radioactive material that undergoes 3.7 × 10^10 (37 billion) nuclear disintegrations per second.
2. The curie is a non-SI unit, but it is still widely used in various fields, including nuclear medicine, radiation protection, and environmental monitoring.
3. The curie is related to the becquerel, the SI unit of radioactivity, by the conversion factor: 1 Ci = 3.7 × 10^10 Bq.
4. Radioactive decay, which is measured in curies, is a key concept in understanding half-life and radiometric dating.
5. Radiometric dating techniques, such as carbon dating, rely on the known half-lives of radioactive isotopes to determine the age of geological or archaeological samples.

Review Questions

• Explain how the curie is used to measure the intensity of radioactive sources.
  • The curie is a unit of radioactivity that measures the rate of nuclear disintegrations per second. It is used to quantify the intensity or strength of radioactive sources, such as those found in nuclear medicine, radiation therapy, and environmental monitoring. By measuring the activity of a radioactive sample in curies, scientists and technicians can determine the amount of radioactive material present and monitor its decay over time, which is crucial for various applications, including medical treatments and environmental safety.
• Describe the relationship between the curie and the concept of half-life in the context of radiometric dating.
  • Radiometric dating techniques, such as carbon dating, rely on the known half-lives of radioactive isotopes to determine the age of geological or archaeological samples. The curie, as a measure of radioactivity, is directly related to the concept of half-life, which is the time it takes for a radioactive substance to lose half of its radioactivity through decay. By measuring the remaining radioactivity of a sample, expressed in curies, and knowing the half-life of the radioactive isotope, scientists can calculate the age of the sample using radiometric dating methods. The curie, therefore, plays a crucial role in the application of these dating techniques, which are essential for understanding the geological and archaeological history of the Earth.
• Analyze the significance of the curie being named after the renowned physicist and chemist Marie Curie, and how this reflects the historical development of our understanding of radioactivity.
  • The curie, as a unit of radioactivity, is named after Marie Curie, a pioneering physicist and chemist who, along with her husband Pierre Curie, made groundbreaking discoveries in the field of radioactivity. The naming of the curie after Marie Curie reflects the significant contributions she and her husband made to the understanding of radioactive phenomena, which laid the foundation for the development of modern nuclear science and technology. By honoring Marie Curie in this way, the curie unit serves as a testament to the crucial role that women have played in the advancement of scientific knowledge, particularly in the early stages of the study of radioactivity. This recognition of Marie Curie's achievements highlights the importance of diversity and inclusion in the scientific community, and the lasting impact that individual scientists can have on our understanding of the natural world.

Related terms

Radioactivity: The spontaneous emission of radiation, such as alpha particles, beta particles, and gamma rays, by certain unstable atomic nuclei.

Becquerel:

The SI unit of radioactivity, named after the French physicist Henri Becquerel, which measures the rate of radioactive decay.

Half-life: The time it takes for a radioactive substance to lose half of its radioactivity through decay.