The hydrogen atoms in you were produced in the big bang, and the carbon, nitrogen and oxygen atoms were made in burning stars. The very heavy elements in you were made in exploding stars. The size of an atom is governed by the average location of its electrons. If the nucleus were the size of a peanut, the atom would be about the size of a baseball stadium. If we lost all the dead space inside our atoms, we would each be able to fit into a particle of lead dust, and the entire human race would fit into the volume of a sugar cube.
As you might guess, these spaced-out particles make up only a tiny portion of your mass. The mass of the quarks, which comes from their interaction with the Higgs field, accounts for just a few percent of the mass of a proton or neutron. Gluons, carriers of the strong nuclear force that holds these quarks together, are completely massless. Your body is a small-scale mine of radioactive particles. You receive an annual millirem dose from the natural radioactivity originating inside of you.
It is probable that most of the matter in the universe is in the form of ions. The number of neutrons in the nucleus is in many cases approximately equal to the number of protons. A small number of atoms may combine to form a molecule such as water H 2 O or carbon dioxide CO 2. The arrangements and rearrangements of atoms in molecules form the domain of chemistry.
A solid consists of a regular array or lattice containing a very large number molecules or atoms. A typical number of atoms in a piece of matter on a human scale is 10 Physical properties of matter include hardness, malleability, color, and melting point. The important point here is that chemical and physical properties of matter depend only on the electron cloud surrounding the atoms. Therefore they depend only on the number of protons in the nucleus. This number is symbolized by Z, and is called the "atomic number".
Constituents: protons, neutrons, electrons Electric force holds atom together. Nuclear force holds nucleus together. When you see illustrations of atomic orbitals, they're basically showing you the wave-like shape of the individual electrons.
The each s orbital red , each of the p orbitals yellow , the d orbitals blue and the f orbitals If you were to send a high-energy photon or particle in there to interact with an electron, sure, you could pin down its position precisely. But — and here's where quantum mechanics trips most of us up — the act of sending that high-energy particle in there fundamentally changes what's going on inside the atom itself.
It causes the electron to behave like a particle, at least for the moment of that one interaction, instead of like a wave. But until such an interaction occurs, the electron has been acting like a wave all along. When you have an isolated, room temperature atom, or a chain of atoms linked up in a molecule or even in an entire human body, they're not acting like these individual particles with well-defined points. Hydrogen density plots for an electron in a variety of quantum states. While three quantum numbers The better way to think about an electron is like a "fog" or a "cloud," spread throughout the space around an atomic nucleus.
When two or more atoms are bound together into a molecule, their electron clouds overlap, and the electron's extent in space gets even more diffuse. When you press your hand up against another surface, the electromagnetic forces from the electrons on that surface push against the electrons in your hands, causing the electron clouds to distort and deform in their shapes.
This is counterintuitive, of course, because we're so used to thinking of the fundamental constituents of matter in terms of particles.
But it's better to think of them as quanta instead: behaving like particles under high-energy conditions but behaving like waves under low-energy conditions. When we're dealing with atoms under normal terrestrial conditions, they're wave-like, with individual quanta occupying large volumes of space all on their own. If you took an atomic nucleus and bound only one electron to it, you would see the following The electron is never located in one specific place at one particular time, but rather exists in a cloud-like or fog-like state, spread throughout a volume of space representing the entire atom.
There's a big problem whenever we rely on our intuition to make sense of the Universe: intuition is borne from experience, and our own personal experience of the Universe is entirely classical. Our Universe is made up of particles at a fundamental phenomena, and collections of particles can compress, rarify, and oscillate in ways that appear wave-like.
But down in the quantum realm of atoms, photons, and individual electrons, wave-like behavior is just as fundamental as particle-like behavior, with only the conditions of the experiment, measurement, or interaction determining what we observe. At very high energies, experiments can reveal that particle-like behavior we're so familiar with.
But under normal circumstances, like the ones we consistently experience in our own bodies, even an individual electron is spread out over an entire atom or molecule. After a very short while they lose this gained energy, perhaps as light again. Changes in the patterns of absorbed and reflected light give reflections and colours - so we see the table as solid. So why does a table also feel solid? Many websites will tell you that this is due to the repulsion — that two negatively charged things must repel each other.
But this is wrong, and shows you should never trust some things on the internet. It feels solid because of the dancing electrons.
As the electrons in one atom get close enough to the nucleus of the other, the patterns of their dances change.
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