Millicurie (mCi)

Definition

A millicurie (mCi) is a unit of radioactivity equal to one-thousandth of a curie. It measures the rate of radioactive decay or disintegration of unstable atomic nuclei.

5 Must Know Facts For Your Next Test

1. One millicurie (mCi) is equivalent to 37 million disintegrations per second.
2. Millicurie is commonly used in medical and biological applications, such as radiopharmaceuticals.
3. The unit curie, and by extension millicurie, is named after Marie and Pierre Curie for their work in radioactivity.
4. 1 mCi = $3.7 \times 10^{7}$ becquerels (Bq), where one becquerel equals one disintegration per second.
5. Radiation doses from sources measured in millicuries can have significant biological effects depending on exposure duration and type of radiation.

Review Questions

• How many disintegrations per second are there in one millicurie?
• What medical applications commonly use measurements in millicuries?
• Convert 2 mCi to becquerels.

Related terms

Curie (Ci): A unit of radioactivity defined as $3.7 \times 10^{10}$ disintegrations per second.

Becquerel (Bq): The SI unit for measuring radioactive decay, defined as one disintegration per second.

Half-life: The time required for half the atoms in a radioactive substance to undergo decay.