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Neutrons bind with protons and one another in the nucleus through the strong force, effectively moderating the repulsive forces between the protons and stabilizing the nucleus.$^{[1]}$ $\ce{^2He}$ (2 protons, 0 neutrons) is extremely unstable, though according to theoretical calculations would be much more stable if the strong force were 2% stronger. Its ...


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In a few more words, physicists right now are confident in saying that there are four fundamental things that happen: Protons and neutrons stick together. (The "strong nuclear interaction".) Neutrons sometimes "fall apart" into a proton, electron, and antineutrino. Sometimes this can happen in reverse, too. (The "weak nuclear interaction", also known as "...


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Your chemistry teacher is making a few simplifications there that make the statement false on a black-and-white true-and-false scale. Protons would repel each other electrostaticly due to their same charges. Neutrons interact with protons by the so-termed strong interaction (because it is stronger than the weak interaction; props to physicists for inventing ...


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When beryllium is bombarded with alpha particles, where do the electrons come from to make the carbon stable? Nowhere. This is a nuclear reaction, not a chemical one. Charge is conserved and no extra electrons were supplied. The carbon nucleus is stable with respect to nuclear decay. Chemical stability relates only to the behavior of electrons with ...


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@Jan's put up a nice and crisp, answer. My answer is merely a supplement to that ;) It's because the hydrogen ("protium", if you will) nucleus has no need for neutrons. What's this "need for neutrons", you ask? Every element (apart from hydrogen) has multiple protons (it's the number of protons in a given nucleus that allows physicists and chemists to ...


9

Protons and neutrons are both baryons, subatomic particles composed of three quarks. Quarks are smaller fermionic particles that make up protons, neutrons, and other hadrons. Electrons are leptons, fermions that are not composed of quarks. Quarks have mass, spin, charge, and (confusingly) color charge. Color charge is a quantum property that quarks have, ...


6

The electrons are there, all around and intermingled with the nuclei. They maintain the requirement of charge neutrality but, at the temperatures in stellar cores, they don't do much else because there is too much thermal energy and entropy to stabilize complete atoms. So in studying reactions, we ignore them as we would a "spectator species" in an ...


6

In chemistry, the neutrons are important as they determine the spin of a nucleus which determines if and how it is observable by NMR. Like 1H is spin 1/2 and 2H is spin 1. The neutron also adds mass to the atom. In chemical reactions however, the nucleus is not involved and nuclear reactions are more a topic in physics.


4

The typical binding energy per nucleon $(E_\mathrm B/A)$ of most nuclides is about $5{-}8\ \mathrm{MeV}$. Such values are higher than the released energy of a typical radioactive decay. Therefore, emission of neutrons doesn’t occur during most usual radioactive decay processes. In order to make a neutron source, you have to find a suitable target (not $^{...


4

Atomic weights in any periodic table are based on the natural abundance of different isotopes of the element. But sometimes the source matters and the results will be different. The most important thing to note here is that creating new isotopes is hard. You can't just "add" neutrons to an atomic nucleus and often when you do it decays to a different ...


4

The key here is that a system will tend towards the lowest energy state; in other words, for a process to be spontaneous, the final state must have lower energy than the initial state. The mass of a neutron is slightly higher than the combined mass of the proton, electron and neutrino that result from beta decay, meaning that the decay will be energetically ...


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Electromagnetic radiation consists of electromagnetic waves (oscillations of the electric and magnetic field), whereas corpuscular radiation consists of actual particles. Certainly, wave–particle duality can make the distinction between waves and particles fuzzy. However, electromagnetic radiation (whether described as wave or as photons) is massless (its ...


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It seems that the gist of the question is about the distance in the force equation for Coulombic attraction. $$ F = k*\frac{q_1 * q_2}{r^2}$$ Naively, as the distance between the charges goes to zero, the force should go to infinity. That obviously doesn't happen. The same problem exists for black holes; the gravity should be at a singularity which doesn't ...


2

The symbols $Z$, $N$, and $A$ are typically used to describe a nucleus: $Z$ : atomic number (= number of protons) $N$ : neutron number $A$ : mass number ($A = Z + N$) There is no fixed $Z:N$ ratio throughout the whole periodic table for stable isotopes, but a belt of stability in the Chart of Nuclides.


2

In the process of stellar nucleosynthesis, the helium comes from deuterium ($\ce{^2H}$) produced through the Proton–proton chain reaction (P-P 1). In P-P 1, two proton ($\ce{^1H^+}$) atoms fuse to form one deuterium atom, as well as a positron ($\ce{e^+}$) and a electron neutrino ($\ce{v_e}$). One deuterium atom and one protium atom fuse, forming one ...


1

As a general matter, it seems possible that neutron isotopes are actually not physically similar to their elements, since, for example, a given isotope might not be stable. It was very well known (pre-1940s) that the number of protons (Z) distinguish one element from the other. If we talk about the simplest element with Z=1, whether it contains 0, 1 or 2 ...


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The atomic weight of an element should reflect the natural isotopic abundance. However there are statistically significantly different sampling variations. If you look at the nuclides the individual isotopes have masses known with much greater precision that the overall atomic weight for the particular element. For example Wikipedia lists atomic weight for ...


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Corrected: "James Chadwik identified the neutron by exposing a Beryllium foil to α-rays (He+2) and showing that the previously discovered emitted collision product were massive neutrally charged particles." The experimental set-up he used (see:http://rspa.royalsocietypublishing.org/content/royprsa/136/830/692.full.pdf) did not determine where any electrons ...


1

Electromagnetic waves are oscillating electric and magnetic fields, oriented perpendicularly to each other and their direction of motion. According to quantum mechanics, the energy of an EM wave is quantized, and each quantum is called a photon (from which the idea of light as a particle is formed). If you look at an EMR spectrum, you will see all the ...


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