What is the formula for the reaction in a smoke detector?

Key Takeaways

Gravity is a force that attracts objects with mass toward each other.
It's responsible for keeping Earth and other planets in orbit around the sun.
The strength of gravity depends on the mass of the objects and the distance between them.

It is more a physical reaction than a chemical reaction. The americium in the smoke detector is emitting high-speed alpha particles (helium nuclei). The particles hit molecules in the air and knock off electrons to form ions. So, for example, you might say:

O₂ + He(+2) --> O₂(+1) + e(-1) + He(+2)

(Charge is indicated inside the parentheses.)

See How Smoke Detectors Work for complete details on the inner workings of smoke detectors.

Here are some interesting links:

Frequently Asked Questions

How does the concept of gravity apply to celestial bodies other than Earth and the sun?

Gravity is a universal force that affects all objects with mass, including celestial bodies such as planets, moons, asteroids and stars.

Is there a way to measure the gravitational force between two objects with precision?

Yes, scientists use tools like the Cavendish experiment, which involves measuring the tiny gravitational attraction between two masses to determine the gravitational constant.