Typically it is an Angstrom, which is 1x10-10 meters
The unit of radius used to measure the size of a circle is typically in units of length, such as inches, centimeters, or meters.
pico meter
mole
pico meter
Any measure of length, such as meters, centimeters, or light-years.
You can measure the diameter, then divide that by 2.
The Watt is the unit used to measure electric power :)
The SI unit used to measure mass is kilograms. It is written as Kg.
A radius is used to measure a circle; squares do not have a radius, they would be measured by a side. If a square has a side that measures 6 inches, then it's area is 36 square inches. Note that without a unit of measurement (inches, or whatever it is) you do not have a meaningful answer.
Radian is the unit used to measure distances around a circle. It is defined as the angle subtended at the center of a circle by an arc equal in length to the radius of the circle.
Answer: their is no unit for measureing atoms that i know of and i am a science teacher. Answer: You should first decide what aspect of an atom you want to measure: its mass, its diameter, its speed, its electronegativity, etc.
A unit of mass used to express atomic and molecular weights, equal to one-twelfth of the mass of an atom of carbon-12. It is equal to approximately 1.66 x 10^-27 kg.