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16 votes

Why is it that protons and electrons undergo the same amount of deflection in an electric field if they have the same energy?

Now that's a mildly non-trivial observation. Why would they be equal, really? Let's say a particle with mass $m$, charge $q$, and initial velocity $v$ enters an area of length $L$ where an electric ...
Ivan Neretin's user avatar
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9 votes
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Why does radioactive matter decay in series of half-lives?

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 ...
matt_black's user avatar
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7 votes
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Proton leak during ATP synthesis

This occurs during Oxidative phosphorylation and the "proton leak" process is also called Uncoupling of Oxidative Phosphorylation The mitochondrial electron-transport chain Electron ...
xavier_fakerat's user avatar
7 votes
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How right is defining elements with the number of protons?

Most of chemistry doesn't care a whit about all of the properties you named: they're in the realm of nuclear physics, as noted by user badjohn. Even radioactive decay is something of a black sheep, ...
hBy2Py's user avatar
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6 votes

Is an acid (just) a proton donor and if not, what is the correct definition of an acid?

Your teacher said that this is not completely correct as there are (at least) three common definitions for acids and bases (Wiki has a good article for this https://en.wikipedia.org/wiki/...
Rampallian's user avatar
6 votes
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My textbook writes hydronium ion as [H(H2O)]+, is this correct?

In water solution context, it is recommended and preferred to use $\ce{H+(aq)}$, as products of proton interaction with water are complex and still subject of research. $\ce{[H(H2O)]+}$ would be ...
Poutnik's user avatar
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5 votes
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How to experimentally measure number of protons or electrons in an element?

Moseley measured the atomic number in 1913 with relatively modest equipment (by modern standards) but I doubt that you could reproduce his experiments in a typical kitchen. Atomic number at ...
badjohn's user avatar
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5 votes

What is the proton NMR spectrum of p-methoxyphenol?

In theory, this structure is expected to provide four different signals: a broad singlet, due to the potential exchange of the phenolic OH a singlet accounting for three protons of the methyl group ...
Buttonwood's user avatar
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5 votes
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Why did J.J. Thomson observe protons in his cathode ray experiment?

Thompson observed more than just cathode rays. He experimented with different gases and different pressures in his tubes. When there is a significant amount of hydrogen you get ionisation of the gas ...
matt_black's user avatar
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5 votes

Why does radioactive matter decay in series of half-lives?

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 ...
Poutnik's user avatar
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5 votes
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What does it mean to accept or donate a proton?

Donate a proton (acting as an acid) A covalent bond with hydrogen breaks, hydrogen leaves without electrons (as a hydrogen ion, sometimes called proton as a shorthand), and the two electrons from the ...
Karsten's user avatar
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5 votes

Neutron–proton ratio and isotope stability

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 ...
Poutnik's user avatar
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5 votes

NH protons not appearing in H NMR spectrum of 3,4-dihydropyrimidone derivative (solvent: CDCl3)

As indicated by @Waylander, your compound may undergo keto-enol tautomerism. Beside a sample which may contain varying concentrations of three compounds (top row), ...
Buttonwood's user avatar
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4 votes

How does one find the probability of tunneling along a reaction coordinate computationally?

If the reaction coordinate $\xi$ can be expressed as the change in the relative position between two groups of the molecule (e.g. for instance as a change in a bond length so that $\xi$ is given in ...
Paul's user avatar
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4 votes

Chemistry: A Chemical Dilemma

You have it a little backwards. We don't observe charge, and then infer the existence of a force. It's the other way around. We observe forces between objects -- they repel or attract each other -- ...
Christopher Grayce's user avatar
4 votes
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Effective Nuclear Charge of Noble Gases

I think that this is basically an accounting problem. The full electron configuration of $\ce{Ne}$ is: $1s^22s^22p_x^22p_y^22p_z^2$. So, what does one now define as core electrons? It could be: "all ...
TAR86's user avatar
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4 votes

Can it be said that on our planet we have roughly the same number of electrons as we have protons?

Yes We can see that the charges in the observable world are close to balance by considering what we would observe if they were not. Big imbalances of charges cause strong electrical fields. Those ...
matt_black's user avatar
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4 votes
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In helium-2, would each electron experience a single positive charge from the nucleus?

To answer this question, I am going to assume that a $\ce{^2He}$ nucleus actually exists long enough for two electrons to surround it — this is probably not a valid assumption since Webelements.com ...
Jan's user avatar
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4 votes
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Is the reaction of calcium carbide with water a Brønsted-Lowry acid-base reaction or Lewis acid-base reaction?

We may regard the calcium hydroxide and calcium carbide as essentially ionic except for the covalent bonding within the anions. So there is no Lewis reaction involving the calcium. That leaves the ...
Oscar Lanzi's user avatar
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4 votes

Why are the protons in the nucleus not repelled by each other?

Protons in nucleus no doubt are repelled by each other. But we know that an atom is stable. The reason for this is that the protons and the neutrons(together called nucleons) are attracted to each ...
Arka Sinha's user avatar
4 votes
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Is water hydronium and hydroxide?

If there are arrows going both ways then that means it’s in equilibrium between the right side (products) and the left side (reactants). It doesn’t mean that water is a mix of H3O+ and -OH, a vast ...
Pasta Man's user avatar
4 votes

Hydrogen Isotopes and Bronsted Lowry Acid

Just remember that titles and names do not matter for elements or atoms. As Shakespeare wrote "What's in a name? That which we call a rose, by any other word would smell as sweet." An ...
AChem's user avatar
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4 votes

Measurement of the number of electrons, protons and neutrons inside an atom

There are no techniques that directly count the number of electrons, protons and neutrons in an atom. All deductions about basic atomic structure were established indirectly, well before the 1940s ...
AChem's user avatar
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4 votes
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How did early chemists work out the number of protons in the nucleus?

The allusion to Moseley's contributions in the comments is only partially correct in a historical sense. It was Antonius van den Broek (a name rarely mentioned in general chemistry) who proposed that ...
AChem's user avatar
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3 votes

In helium-2, would each electron experience a single positive charge from the nucleus?

First of all, helium-2 is an extremely short-lived species - if you wanted to speak about its existence at all. So I assume that you had a more stable isotope in mind, e.g. helium-3 or helium-4. ......
aventurin's user avatar
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3 votes

In helium-2, would each electron experience a single positive charge from the nucleus?

Electrostatic interaction is like gravitation: A spherical charge (or body) gives the same attraction as an equal point charge (or mass) at the centre of the sphere. If you are in the sphere, gravity ...
Karl's user avatar
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3 votes
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Does firing a proton beam on water make it acidic?

No, probably not. pH represents the concentration of hydrogen (/hydronium) ions in water, requiring a negative ion complement. pH could be thought of roughly as a response to things other than water ...
uhoh's user avatar
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3 votes

Does firing a proton beam on water make it acidic?

Yes, the concentration of $\ce{H3O+}$ will increase which will lower the pH value of the water. This is theorie based. In reality you won't be able to measure the change. The mount of protons you ...
Guido's user avatar
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3 votes
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What is the reason why protons and electrons do not collide?

They do collide. But it's not like cars crashing and smashing each other up on the highway. Their quantum mechanical wavefunctions overlap and the electrons do in face settle in with wavefunctions ...
Oscar Lanzi's user avatar
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3 votes
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Why do acids donate protons?

Using the following generic reaction, where an acid donates $\ce{H+}$, i.e. a proton: $$\ce{HX + B <=> X- + HB+}$$ If a lone pair of electrons on $\ce{B}$ has a higher energy than than than ...
SendersReagent's user avatar

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