# Tag Info

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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 ...

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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, ...

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There are fewer decays because there are fewer atoms to decay The simple reason why the number of decays (strictly, the number of decays per unit time) decreases in simple radioactive decay is because there are fewer atoms left to decay. Nuclear decay is probabilistic. The probability of any given unstable atom decaying is constant (independent of time or ...

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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 ...

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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.

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It is a general principle, not limited to nuclear chemistry, but is common for many areas, e.g. for the reaction kinetic of the 1st order. All processes, where the value time rate is proportional to the value, have value time evolution in the form of the exponential function. $$\frac {\mathrm{d}x}{\mathrm{d}t}= -k \cdot x$$ leads to $$x= x_0 \cdot \exp {... 5 In context of this answer, stable means not undergoing a radioactive decay, regardless of the value of measured half-life.(+) For light nuclei till about 40 nucleons, the neutron/proton ratio of stable isobars(the same nucleon count) is generally around 1.0. ( \ce{^3He, T} are quite exception. ) Nuclei too aside from this ratio ( See Valley of stability ) ... 4 Atomic weights in any periodic table are based on the natural abundance of different isotopes of the element. But sometimes the source matters and the results will be different. The most important thing to note here is that creating new isotopes is hard. You can't just "add" neutrons to an atomic nucleus and often when you do it decays to a different ... 3 It seems that the gist of the question is about the distance in the force equation for Coulombic attraction.$$ 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 ...

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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.

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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 helion ...

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Your textbook is wrong and there are several confusions in your argument The first issue is the textbook claim. Which is wrong for two possible reasons. One is that the masses quotes for atoms ni most periodic tables are for the natural abundance of the element given multiple possible isotopes (hydrogen has three: one with a single proton, one with an extra ...

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Deuterium is a stable combination of a proton and a neutron, but it could accept and bind a proton, forming helium-3 or a neutron, forming tritium. Neither reaction would be explosive, in the sense of liberating enough energy to cause some other nuclear reaction. You might be able to make a small explosion as the sudden heat boils something very fast. Now, ...

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In a sense, atoms are "going nuclear" all the time, forming radioactive isotopes under the influence of high-energy particles in the upper atmosphere. In perhaps the best-known example, the bombardment of nitrogen with high-energy neutrons may generate carbon-14, which subsequently enters organic matter before it slowly decays (half-life = 5700 years), ...

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Decaying are like coin tossers It helps me to compare two different mental pictures. The first picture, which is not at all like radioactive decay, is of lighting a fuse. It starts burning at the near end and burns toward the far end at some number of millimeters per second. Each section's chance of burning depends completely on the section before it: the ...

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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 ...

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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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