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For questions about ions - atomic or molecular particles having a net electric charge. Do NOT use this tag just because your question involves ions but is not about the ions themselves (as in electrochemistry, etc.).

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Solutions of ions [closed]

Let's say we have a water solution made of 50 g of NaCl and 50 g KBr. We evaporate solvent. What will crystalise first? Is it possible to know/calculate on for this kind of examples? Thanks brumer
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20 views

Ions concentration of mixed salts

I’m an amateur in chemistry, so I apologize if this is a too basic question. Background: I want to understand a study of sugarcane growth into solutions containing different nutrients. I’m creating a ...
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1answer
23 views

Can the ions of dissolved salts be physically separated with a strong enough external electric field?

Say you had a arbitrary amount of sodium chloride dissolved in water. Could an external electric field (e.g. the electrically charged plates in Millikan's oil drop experiment) physically pull apart ...
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2answers
79 views

Why are some ions mutagenic and others are not?

It is my understanding that when ionic species (such as $\ce{He^2+}$, or alpha particles) enter the human body, they tend to react with biomolecules, causing damage by (for example) mutating DNA. If ...
3
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1answer
65 views

How can I interpret the CH4+ structure?

I am trying to teach myself about Electron Ionization, and am very confused about the formation of the CH4+ Ion. Do the dotted lines between the C and the H, and between the two Hydrogens indicate a ...
2
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1answer
29 views

How to determine net charge of a polycation using Wade's rules?

In order to determine the net charge of polycations, which adopt a Wade-like structure (octahedral, trigonal bipyramidal, ...), Wade's rules can be used. For example, the charge $x$ of the ...
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1answer
41 views

What does it mean when something is said to “contain ions”?

(I'm looking for a very basic level explanation because my only chemistry experience is one fast-paced high school course.) So, according to the professor of that course, ions are never found in ...
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0answers
28 views

What is the arrangement of water molecules in a hydration shell around an anion?

I believe I read somewhere that the hydration shell of ions always has hydrogen on the outside, but I can't relocate the exact whereabouts of this. Thus, I decided to ask here, as to what the ...
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0answers
24 views

How to divide the peaks of two anion ions using ion chromatography?

I used an ion chromatography system (Dionex IC-2000) to determine the inorganic ions and acid from the samples collected in the atmosphere. For measuring $\ce{SO4^2-, NO3, Cl-}$, and low molecular ...
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2answers
68 views

Formula of Manganese (IV) Ion

When determining the formula of manganese (IV) oxide, since it’s made up of $\ce{Mn^4+}$ and $\ce{O^2-}$ ions, why is the formula $\ce{MnO2}$ and not $\ce{Mn2O4}$? Any help would be greatly ...
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1answer
75 views

Very elementary question about valence electrons of ionic compound

In a university entrance question, I found this question: What is the number of valence electrons of $\ce{Mg(OH)2}$? Answer = 24 I know that Mg has 2 valence electrons and O has 6. But I don't ...
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0answers
15 views

How does a negatively-charged ion behave in the electrical field of biphasic systems

The following is the electrostatic potential plot along the z-axis in a liquid-liquid biphasic system (a ionic-liquid vs water). There are some negatively-charged ions in the positive side of z (z > ...
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0answers
32 views

Are dopant ions on a crystal lattice free or bonded?

This question seems simple but I don't seem to find many answers right away for this. When you make a crystal doped with ions (like a luminescent phosphor) and the ions then become a defect in the ...
4
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1answer
55 views

Can we manipulate the rate of water's autoionization?

I just got introduced to this concept and these thoughts came into my mind. Is there a way to increase the equilibrium constant of the autoionization of water?
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1answer
47 views

Is there a blanket term for all variants (both nuclides and ions) of a chemical element?

I'm hoping to catalogue the various nuclides and oxidation states of an element but can't find a single term that describes them all, save for "chemical element variations". Is there a specific term ...
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0answers
35 views

Ionisation energy for ion

I have not understood this line from J. D. Lee.: The ionization energy for an atom is always positive and for an ion may be negative. Why negative when heat is supplied? If I.E. can be negative, ...
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0answers
39 views

How would you write the empirical formula of an ion?

How would you write the empirical formula of e.g. X2Y42-?
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0answers
38 views

Synthesis of Alkalide Ions

How are alkalide molecules synthesized, for example, I have read in a paper that the reaction $\ce{2Na -> Na+ + Na-}$ is exothermic with a $\ce\Delta$H = -438 $\frac{kj}{mol}$ I have also read ...
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1answer
49 views

How does the water pollutant sodium nitrate affect the concentrations of other ions in tap (dam) water? [closed]

Context In my assignment I've been given two water samples from the hinze dam. The first sample has been untouched, however the second has been contaminated with an unknown ionic compound. To ...
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0answers
38 views

How do concentrations of nitrate in water samples change over time?

Context: (Not necessary to answer the question) For an assignment I am currently testing two samples of water. One is a pre-contamination sample and the other is a post-contaimnation sample. Between ...
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0answers
142 views

Compare stability of transition metal cations in aqueous solution

I have to compare the stability of the following transition metal cations: $\ce{Co^3+, Fe^3+, Cr^3+, Sc^3+}$ in aqueous solution. (Source: Joint Entrance Exam (JEE) 2013 Mains India) The first thing ...
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2answers
45 views

Do we consider the dissociation of water when dealing with ion concentrations of a solution?

One mole of hydrated copper(II) sulphate, $\ce{CuSO4 . 5 H2O}$, is dissolved in water. How many moles of ions does the solution contain? 1) 1 2) 2 3) 6 4) 7 The ...
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1answer
42 views

Extracting metallic magnesium from cholorphyll

My understanding is that when chlorophyll is exposed to an increased concentration of hydrogen ions (or rather the pH is lowered), the magnesium is displaced by a hydrogen ion and chlorophyll is ...
4
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1answer
57 views

Why does the helium hydride ion have such a large dipole moment?

According to Wikipedia, the helium hydride ion $\ce {HeH+}$ has a dipole moment of 2.26 or 2.84. What contributes to this large dipole moment in this molecular ion?
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41 views

Bond dissociation energy of the trihydrogen cation

Recently, in one of the questions in an assignment on the topic of energetics, we were asked to explain why the bond dissociation energy for the trihydrogen cation is much larger than what we would ...
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1answer
106 views

Does tetraoxidovanadium (VO4+) ion exist?

In my book (NCERT India), it is mentioned that: (page 224) ...$\ce{Mn2O7}$ gives $\ce{HMnO4}$ and $\ce{CrO3}$ gives $\ce{H2CrO4}$ and $\ce{H2Cr2O7}$. $\ce{V2O5}$ is, however, amphoteric though ...
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1answer
201 views

What is the difference between nuclear charge and ionic charge?

There was a question asking why magnesium metal has a higher melting point than sodium. In the answer, they said: Magnesium has more delocalised electrons. Magnesium ions have a greater ...
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1answer
33 views

How to determine which ions will pair to form a compound in an aqueous solution?

Let us assume we have an aqueous solution with the ions $\ce{A+}$, $\ce{B+}$, $\ce{C-}$ and $\ce{D-}$. Which ions will form a bond and why? Will the compound formed be $\ce{AC}$ and $\ce{BD}$ or $\ce{...
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0answers
27 views

Different values of concentration of product at equilibrium

$\pu{60g}$ of acetic acid and $\pu{46g}$ of ethyl alcohol are mixed with each other at a constant temperature and allowed to attain equilibrium. At equilibrium $\pu{58.2g}$ of ethylacetate and $\pu{...
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3answers
125 views

Are ions actually charged particles?

For instance, if an atom loses an electron and becomes a cation, such as sodium, how does that make the sodium atom positively charged? The sodium's atomic radii decreases due to less electron-...
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0answers
74 views

Identification of compound of potassium and oxygen based on flame color

When a flame test was carried out on A, it gave a lilac flame. Also, a glowing splint was re-lit during testing. This assumes that the substituents of the compound are potassium and oxygen. Identify a ...
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2answers
54 views

Is it possible to prevent sacrificial anode contaminate the soil?

I have mild steel pipe (black pipe, NOT zinc plated) water well. My question is, is it possible to somehow put sacrificial anode in electrolyte which is contained in some bucket instead of burring it ...
4
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1answer
113 views

Why are fluoride ions (and ions in general) reactive?

Please bear with me—-I have a pretty meager background in chemistry but am trying to learn some! My question is about ion reactivity—-specifically of the reactivity of $\ce{F-}$. I often hear that ...
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0answers
101 views

Which is more conducting - molten sodium chloride or molten magnesium chloride? [closed]

Which is more conducting - molten sodium chloride or molten magnesium chloride? I'm pretty sure I know the answer to this but my problem is putting into words. Magnesium is more conductive due to its ...
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2answers
215 views

What are the IUPAC names for singly- and doubly-protonated piperazine?

If ammonia, $\ce{NH3}$, is protonated, it becomes ammonium: $\ce{NH4+}$. If piperidine is protonated, it becomes piperidinium: If piperazine is protonated once, what does it become? By analogy, I ...
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0answers
29 views

Which is a better measure of polarising power of a cation?

Recently, I have come across literature stating that polarising power of a cation is proportional to the inverse of the surface area $(4\pi r^{2})$ while some associate it with the charge density of ...
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0answers
47 views

Relative concentrations of ions in acid-base reaction

An aqueous solution of ammonia has of pH = x, and a solution of hydrochloric acid has pH =y; it is also known that x + y = 14, and x > 11. If equal volumes of these two solutions are mixed together, ...
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1answer
51 views

Calculating the change in pH upon diluting an acid

What volume of water is added to $\pu{400 ml}$ of $\ce{HCL}$ solution so that the pH of the solution increases by 1 unit This is how far i went but the answer says $\pu{1000 ml }$ where am I wrong is ...
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1answer
106 views

Why does copper gain electrons in redox reactions, when it instead has a tendency to lose them? [closed]

Cu has tendency to lose electrons. But in some redox reactions, it gains 2 electrons and become neutral. Why is it so? How can it gain them?
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QM modelling of charge separation reactions

I have a general question regarding the modelling of reactions in which neutral reactants form charged species/ions (in solution). How can one get the energetics approximately right on reactions like ...
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1answer
83 views

Why is potassium cation harder than copper?

According to HSAB theory, the smaller radius and the less polarizable an acid is, the harder it is. According to Wikipedia, the ionic radii of $\ce{ K+}$ is much larger than $\ce{Cu+}$, which makes ...
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2answers
338 views

Why are H+ and OH- ions preferentially discharged in the electrolysis of NaCl(aq)?

There are 4 types of ions in an $\ce{NaCl(aq)}$ solution: $\ce{H+}$, $\ce{OH-}$, $\ce{Na+}$ and $\ce{Cl-}$. According to the E.C.S. table, $\ce{H+}$ and $\ce{OH-}$ should preferentially discharge at ...
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2answers
318 views

Why does acetic acid (CH3COOH) conduct electricity the worst in comparison to HBr, HCOONa and NaNO3 [closed]

Which of the given substances (in an aqueous solution) conducts electricity the worst: $\ce{CH3COOH}$, $\ce{HBr}$, $\ce{HCOONa}$ and $\ce{NaNO3}$? I've found this assingment included in the 2017 ...
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0answers
61 views

Among [PCl4]+ and [PCl4]- which is more thermodynamically stable?

According to my textbook, in $\ce{[PCl4]+}$ phosphorus exists in +5 state and in $\ce{[PCl4]-}$ phosphorus exists in +3 state. Which of these ions is more stable in terms of standard enthalpy of ...
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0answers
13 views

Acid/base separation in nanofiltration

How do semi-permiable membranes handle salts that can separate into an acid and a base based on the "rules" of the membrane? For example, say I have a nanofiltration membrane that rejects ...
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0answers
86 views

Bond angles in a oxonium cation

What are the bond angles in protonated alcohol? The bonds in the carbon chain are presumably unaffected by the $\ce{-O^{+}H2}$ group and so in their usual tetrahedral arrangement; what are the angles $...
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1answer
714 views

How can Phosphate be charged at -3? [closed]

I am studying chemistry in High School and I am studying my ions(Because I failed too in the beginning, oops) and I have a question on this reasoning: In Phosphate(PO4), it has a charge of -3. The ...
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1answer
133 views

Why does cobalt have no negative charge?

I would like to know why cobalt cannot have a negative charge (or at least why a negative charge for cobalt isn't typical). I am not sure where I have gone wrong in my reasoning. The electronic ...
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0answers
18 views

Resistance of Electrolytes [duplicate]

During electrochemical experiments, we consider the resistance of the electrolytes. What exactly is causing the electrolytes to offer resistance to flow of charges in them? Also, does the resistance ...
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2answers
342 views

Why doesn't 4 hydrogen and 1 carbon form a ionic bond? What is the limit of electrons that can be given away?

I understand that it's a covalent bond, but to my uneducated mind isn't it possible to have the carbon give 1 electron to each of the hydrogens and form an ionic bond instead? I read this response ...