How big is an atom?

The radius of a typical atom is one tenth of a billionth of a meter. A string of atoms one meter (about 3 ft) long contains an atom for every person in the world. A cube of sugar contains as many atoms as there are stars in the Universe. read more

It is 3,000 times too big! My offer turns out to be very far from generous. As many atoms of gold as seconds since the big bang amounts to a speck of gold weighing 0.14 milligrams and worth 0.21 cents. read more

An atom is the smallest constituent unit of ordinary matter that has the properties of a chemical element. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are very small; typical sizes are around 100 picometers (a ten-billionth of a meter, in the short scale). read more