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Particle Physics
Relatively recent experimental results have confirmed what philosophers throughout history had theorized all along; that all matter is made up of elementary particles. Those curious about this cutting-edge field of physics known as particle physics should post their questions here, including those about fundamental particles, fundamental forces, Grand Unified Theories, and the extraordinary devices that have been or need to be engineered to research them.
3,842 Questions
What is the difference between a proton and antiproton?
The difference between a proton and a positron is threefold. First, the proton is much more massive (a bit over 1800 times) than a positron. Second, the positron is an elementary particle (though it is antimatter), while the proton is made up of three elementary particles called quarks (two up quarks and one downquark). Third, the positron is antimatter while the proton is "regular" matter. Protons are stable particles (they are hydrogen-1 nuclei), and positrons are produced in positron emission (a type of radioactive decay) or in pair production (where a high energy gamma ray "splits" into an electron and a positron when passing near an atomic nucleus). After a positron appears, it will eventually (and in a relatively short period) combine with an electron in an even called mutual annihilation, and both particles will be converted into energy.
Both the proton and positron have a charge of +1, and you can review more information by using the links below to the related questions about the proton and the positron.
AnswerA proton is a particle found in the nucleus. It has a positive charge of +1. (Depending on how versed you are, this is equivalent to + 1.60 x 10-19 C of charge). The proton actually is comprised of three smaller subatomic particles called quarks, two up quarks (+2/3) and one down quark (- 1/3). The electron on the other hand is a fundamental particle in that it is not made up of anything smaller (that we know of yet). It has a -1 charge (again - 1.60 x 10-19 C). A positron, however, is antimatter. It is the antimatter of an electron. For intents and purposes it is an electron with a positive charge. If an electron and a positron should interact, they would annihilate one another.
How do you calculate the amount of protons or neutrons in an element?
well you look at the periodic table of elements. the atomic number equals the number of protons. Then subtract the number of protons from the atomic mass (both protons and nuetrons have atomic mass units of 1 and electrons equal 0). That will give you the number of nuetrons.
What subatomic particle has negligible mass and travels around outside the nucleus?
An electron has negligible mass and moves around the outside of the nucleus in an atom. Electrons are negatively charged particles that play a key role in chemical reactions and electricity conductivity.
How many protons neutrons and electrons are in H2O?
A water molecule has two hydrogen atoms and one oxygen atom. The proton, neutron and electron count of them are 1,0,1 and 8,8,8 respectively. Therefore a molecule of water has 10 protons, 8 neutrons and 10 electrons.
What does the atom whose outer electron shells contain eight electron tend to do?
When an atom's outer shell of rlectrons is full, it becomes non reactive and stabilized. Not every atom can gain an octet though. Hydrogen only has an S1 suborbital and therefore only holds 2 electrons stabley. If 6 extra electrons are forced on, which is EXTREMELY difficult and unnatural, then yes you achieve an octet, but the electrons will leave quickly and the hydrogen will react.
What does the electron produce when they change energy levels?
When electrons change energy levels, they emit light or energy in the form of electromagnetic radiation. This emitted light can have specific frequencies or colors, depending on the difference in energy levels that the electron undergoes.
What is the name of the scientist that discovered the neutron?
In 1920, Ernest Rutherford created a hypothesis about the existence of neutrons. However, it is believed that the neutron was first discovered in 1932. The person credited with this discovery was Sir James Chadwick.
How many protons and neutrons are in oxygen-17?
8 protons and 9 neutrons (total is the atomic mass number 17). In a neutral atom, 8 electrons.
Oxygen-17 is the rarest of the three stable natural isotopes. Most oxygen is oxygen-16 with 8 neutrons.
How can an electron have mass but does not have an diameter?
It has no diameter because it is a point particle (it has nothing inside it). It has mass because the mass has been measured experimentally. If this is hard to imagine, science has lots more concepts even harder.
What does the weak nuclear force act on?
The weak force is the one that allows a quark to turn into a different flavor of quark, thus allowing a neutron to transform into a proton, or a proton to transform into a neutron. In the case of the neutron, one of its down quarks change to an up quark, emitting a W- boson in the process. The boson is itself unstable and rapidly decays into an electron and an electron antineutrino. In the case of the proton, one of its up quarks changes into a down quark, and a W- boson appears briefly, then transforms into a positron and an electron neutrino. If any of this sound familiar, it is because this is the mechanism behind beta decay. There are two kinds of beta decay (beta plus and beta minus), and you can review them and related material by using the links below to related questions.
Which of the three radioactive particles can go through matter the best?
Alpha particles can be stopped by a piece of paper, beta particles can penetrate through skin but can be stopped by a sheet of aluminum, while gamma rays are the most penetrating and can pass through most materials, requiring dense materials like lead or concrete to be stopped.
What is a subatomic particle that is part of a structure of the atomic nucleus?
Atomic nuclei have two kinds of subatomic particles, which are protons and neutrons.
What did Thomson call electrons?
Thomson believed about atoms, that :
An atom consists of a sphere of positive charge with negatively charged electrons embedded in it.
Positive and negative charges in an atom are equal in magnitude, thus an atom is electrically neutral and it has no overall + or - charge.
Not exactly.
Accelerate particles to high speeds: yes.
Create new elements: it is not new elements, but new particles that are created.
Fuse together: this is not so much about particles fusing together; rather, the new particles are created from the energy of the impact. Remember that every energy has a mass equivalent. For example, the LHC is planned to increase its energy to 6.5 TeV per beam, meaning that two particles - two protons for example - will collide at a combined energy of 13 TeV. This corresponds to a mass of about 14,000 protons. This makes it possible to create new particles, including particles that are quite massive.
The electromagnetic force is responsible for joining atoms together to form molecules. It acts between charged particles (such as electrons and protons) and is essential for the interactions between atoms that lead to the formation of chemical bonds.
Where do electrons protons and neutrons reside within an atom?
Protons and neutrons reside within the nucleus, electrons orbit around the nucleus.
What is The repulsive force between proton-proton pairs inside the nucleus is called the?
The repulsive force between proton-proton pairs inside the nucleus is called the electrostatic repulsion force. This force arises due to the positively charged protons within the nucleus experiencing mutual repulsion because they all have the same charge.
When bismuth 214 emits a positron the remaining daughter nucleus is what?
When bismuth-214 emits a positron, it undergoes beta-plus decay to produce polonium-214. This decay process involves the conversion of a proton into a neutron, releasing a positron and a neutrino.
Do the red balls means neutrons?
One cannot really answer this question without additional information. In what picture do red balls mean neutrons?
It is true that in some pictures of an atomic nucleus the color red is used for neutrons, but this is a convention, it is semantics, neutrons themselves have no color (they don't even directly interact with light).
Where is the subatomic particles located?
Subatomic particles, such as protons, neutrons, and electrons, are located within the atoms that make up all matter. Protons and neutrons are found within the nucleus of an atom, while electrons orbit the nucleus in energy levels.
When the number of electrons and protons in a sample of matter are equal the matter is?
neutral.
Positive and negative charges cancel each others.
Does the carbon14 have more protons neutrons or electrons than carbon12?
Carbon-14 contains more neutrons compared to carbon-12. Carbon-12 has 6 neutrons, while carbon-14 has 8 neutrons. The number of protons and electrons in both carbon isotopes remains the same, at 6 each.
Are neutrons found only in atoms?
No, neutrons are not only found in atoms. Neutrons are subatomic particles and can also exist independently in environments such as nuclear reactors or certain types of particle accelerators.
Neutrons are neutral particles as they do not carry any electrical charge. This makes them unique compared to protons, which are positively charged, and electrons, which are negatively charged.
How is an electron formed from energy quanta?
Electrons are not formed from energy quanta; they are elementary particles that exist as fundamental units of matter. However, electrons can be created in processes such as beta decay, where a neutron transforms into a proton, electron, and an antineutrino. These processes involve the conversion of energy into matter, following the principles of quantum mechanics.
