Curie (unit) facts for kids

The curie (symbol Ci) is a unit of measurement that helps us understand how much radioactivity something has. Imagine radioactivity as tiny particles or energy being given off by unstable atoms. The curie measures how many of these tiny "decays" happen every second.

Specifically, 1 curie means there are 37,000,000,000 (37 billion) decays happening every single second! This amount is roughly equal to the radioactivity from 1 gram of a special type of radium called ²²⁶Ra.

What is Radioactivity and Why Measure It?

Radioactivity is a natural process where unstable atoms release energy and particles to become more stable. This energy can be useful in medicine, like for X-rays or treating illnesses, but it can also be harmful if not handled carefully. That's why measuring radioactivity is so important! Scientists and doctors need to know exactly how much radiation is present to use it safely and effectively.

Who were Marie and Pierre Curie?

The curie unit is named after two famous scientists, Marie and Pierre Curie. They were pioneers in studying radioactivity. Marie Curie was a brilliant physicist and chemist who did groundbreaking research on radioactive elements like radium and polonium. She was the first woman to win a Nobel Prize and the only person to win Nobel Prizes in two different scientific fields! Their work helped us understand a lot about atoms and the powerful energy inside them. Because of their amazing discoveries, the unit of radioactivity was named in their honor.

The Becquerel: A New Standard Unit

Even though the curie was very important for a long time, scientists later created a new, more modern unit for measuring radioactivity. This new unit is part of the International System of Units (SI), which is a worldwide standard for measurements. This new unit is called the becquerel (Bq).

The becquerel is simpler to understand because it's defined as just one decay per second. So:

• 1 becquerel (Bq) = 1 decay per second

Since 1 curie is 37,000,000,000 decays per second, this means:

• 1 Ci = 3.7×10¹⁰ Bq
• This can also be written as 1 Ci = 37 Gigabecquerels (GBq), because "Giga" means a billion!

And if you want to know how many curies are in one becquerel:

• 1 Bq = 2.70×10⁻¹¹ Ci (which is a very, very tiny fraction of a curie!)

The International Commission on Radiological Units suggested using the becquerel as the main unit in 1962, but the curie is still sometimes used, especially in older texts or specific fields.

See also

• In Spanish: Curio (unidad) para niños