What is an atom | Matter | Physics | FuseSchool

[Music] atoms are tiny particles that are so small they're not possible to see with the naked eye and they're only possible barely to make out with the most powerful microscopes everything that exists in our universe is made up of atoms including you i and the device you're watching this on in fact there are about 7 billion billion billion atoms in your body alone which is 7 times 10 to the 27 atoms but what is an atom in this video we are going to look at what atoms are made of and the mass and

size of atoms and the arrangement of electrons in an atom atoms may be tiny particles themselves but they are made of even smaller particles called subatomic particles atoms consist of a central nucleus that contains protons and neutrons protons are positively charged and neutrons have no charge this makes the nucleus overall positively charged much like how the sun has planets orbiting it the nucleus has electrons orbiting electrons have a negative charge

because electrons are negatively charged and the nucleus is positively charged they are electrostatically attracted to each other like how gravity ensures attraction between planets and the sun so that's the general structure of an atom what about its mass and size protons and neutrons have the same mass but electrons are so small they weigh almost nothing in comparison to protons and neutrons in fact they are around 2 000 times lighter as a result the massive electron is

concentrated at its nucleus so that's the mass of an atom let's talk about its size one way to describe the size of an atom is its radius the radius of an atom is the distance from its center where its nucleus is to the outermost shell of electrons the radius of an atom is typically 10 to the power negative 10 meters which is very small so the majority of the mass of an atom is contained in its nucleus but in terms of size the nucleus is much smaller than the atom as a whole in fact electrons

can orbit really far away from the nucleus if the atom was the size of a sports arena the nucleus could be the size of a p in the middle let's finish off by looking at the electrons in little more detail negatively charged electrons orbit around the positive nucleus in specific orbits or shells different atoms have different numbers of shells or orbitals [Music] each shell is of a specific energy level meaning an electron must possess a certain amount of energy to reside in a certain shell

electrons and shells closest to the nucleus have the least energy and electrons in the altimeter shell have the highest energy levels in other words electrons orbit the nucleus similar to how planets orbit the sun however electrons can only orbit at specific distances and with specific energies we will look at the differences in structure of atoms of different elements and the periodic table in this video so there we have the structure of an atom atoms have a positively charged nucleus

made up of positively charged protons and neutrally charged neutrons which is orbited by negatively charged electrons the majority of the mass of an atom is found in the nucleus and the typical size of atoms is 10 to the power negative 10 meters to learn about how we discovered the existence of atoms and the structure of atoms watch this video