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Course: High school chemistry > Unit 1
Lesson 1: Atomic structureProtons, neutrons, and electrons in atoms
Atoms are made up of three types of subatomic particles: protons, neutrons, and electrons. Protons and neutrons are found in the nucleus, the dense region at the center of an atom. Electrons are found outside the nucleus. Protons are positively charged and have a mass of about 1 u. Neutrons are neutral (have no charge) and also have a mass of about 1 u. Electrons are negatively charged and have a much smaller mass of about 0.0005 u. Created by Khan Academy.
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Everything in our planet Earth is made out of protons, neutrons and electrons?(6 votes)
No, there are other elementary particles that make up other materials, for example light is made up of photons, energy particles that transmit energy.
In fact, let me elaborate a bit more. There are all kinds of other particles on Earth. Let me list some:
Muons: These are heavier cousins of electrons, often produced in cosmic rays or particle accelerator experiments.
Neutrinos: These are extremely light, neutral particles that rarely interact with matter.
Positrons: These are positively charged counterparts to electrons.
Gluons: These are particles that mediate the strong nuclear force, which binds protons and neutrons together in the atomic nucleus.
W and Z bosons: These are particles that mediate the weak nuclear force, responsible for radioactive decay.
Quarks: These are fundamental particles that make up protons and neutrons, as well as other particles called hadrons.
Leptons: These are a class of particles that includes electrons, muons, and neutrinos.(14 votes)
At1:49, What instrument is used in measuring the mass of a subatomic particles(3 votes)
The mass of a subatomic particle can be measured by using a mass spectrometer. Khan Academy has a lesson on mass spectrometry in the AP®︎/College Chemistry course.(9 votes)
So while electrons make up most of the volume of an atom, protons and neutrons make up most of the mass of an atom?(3 votes)
Most of the volume of an atom is made up of the space around the nucleus in which the electrons orbit.(4 votes)
- Everything in our planet Earth is made out of protons, neutrons and electrons?(3 votes)
All atoms are. Something examples that are not made of protons, neutrons, and electrons are light (EM radiation) and forces.(4 votes)
How do scientists measure the mass of each proton neutron and electrons in an atom, and can scientists measure the volume of each electron cloud, and if they can why would they want to do that?(3 votes)- The mass of protons and neutrons is measured using a technique called mass spectroscopy. In this method, a sample containing atoms is ionized, meaning electrons are removed from the atoms to form charged particles. These ions are then accelerated by an electric field and passed through a magnetic field. The magnetic field causes the ions to deflect, and the amount of deflection is determined by their mass-to-charge ratio. By measuring the deflection and knowing the charge of the ion, scientists can calculate the mass of the proton or neutron.
The mass of electrons is much smaller compared to protons and neutrons, and they are more difficult to measure directly. Instead, scientists use a method called cyclotron frequency measurement. In this technique, a magnetic field is applied to a beam of electrons, which causes them to travel in a spiral path. By measuring the frequency at which the electrons complete each spiral, scientists can calculate their mass using equations based on electromagnetic principles.
Lastly, the electron cloud does not have a specific volume, remember, it is an electron PROBABILITY cloud, calculated by using the Schrodinger equation, so it does not have a defined volume.(3 votes)
My question is why do atoms even exist, What IF there's more we have to come to discover or know? I know people have looked into it but what if there's more then we see?(3 votes)
The Atoms Are basically everything but
you never know it(2 votes)
- why is it 1+ and 1- instead of +1 and -1 for the charge on the subatomic particles(3 votes)
- Do atoms make gasses?(2 votes)
Yes, atoms compose gasses. Every thing that we interact with is made up of atoms.(2 votes)
I have an important question:0:03, she said, “everything is made out of atoms.” Is light made of atoms?(1 vote)
Light itself is not made of atoms, but particles. However, they do play a role in emitting and absorbing light.(4 votes)
When were the first atoms created again? I was hearing about this "Big Bang" thing but I am not very sure. Can someone please explain to me? Also, what are quarks?(2 votes)
After seeing h's answer, I must attempt to answer this question.
1. All matter and energy originated in the Big Bang. Which is the prevailing theory among scientists that all matter and energy in the universe exploded out of nothingness from a single point and is evidenced by how all matter and energy is calculated to be still moving away from that same point. Energy and matter are convertible in this theory. After the big bang, first subatomic particles, and then atoms began to form from energy.
2. Quarks are small subatomic particles that are found in other subatomic particles. Protons and neutrons are made up of quarks.(2 votes)
1:49Video transcript
- [Instructor] Everything in
our world is made up of atoms. Yep, everything. From the air we breathe
to the water we drink, even the materials inside our cellphones. But what are atoms exactly? What's inside of these atoms? What makes an atom an atom? Atoms are tiny particles that
are basic units of matter, like building blocks. But atoms themselves are made up of even smaller subatomic particles, called protons, neutrons, and electrons. Let's take a look at
the simplified diagram to learn more about
these subatomic particles and the structure of an atom. In the center of an atom,
we have the nucleus, which is composed of protons and neutrons. Outside the nucleus, we
have the electron cloud. This is where electrons are
most likely to be found. I've drawn the nucleus much
larger than it really is, but an atom's electron cloud can be 100,000 times larger than its nucleus. So the electron cloud actually makes up most of the atom's volume. Protons, neutrons, and electrons differ in terms of their charge and mass. Let's take a look at charge first. Protons have a positive
charge of one plus, and electrons have a
negative charge of one minus. These charges are equal and opposite, so when protons and electrons
are paired in atoms, their charges cancel. Neutrons have no charge,
which means they are neutral. What about mass? The unit we use to express the masses of subatomic particles is
the unified atomic mass unit, abbreviated as U. Protons and neutrons have
a similar mass about one U. In comparison, electrons have a mass of about 0.0005 U, which makes them roughly
2,000 times smaller than either a proton or a neutron. This means that nearly all the mass of an atom resides in the nucleus, and not in the electron cloud. Atoms make up everything in our world, even though the air we
breathe, the water we drink, and the cellphones we use all look really different from one another, the atoms that make up these
things are all composed of the same subatomic particles; protons, neutrons, and electrons.