An atom or molecule in which the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge. An ion consisting of a single atom is an atomic or monatomic ion; if it consists of two or more atoms, it is a molecular or polyatomic ion.

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Explain why these ions are more strongly hydrated in an aqueous solution?

Note-I've already answered this question. All I want to know is if my reasoning is correct. Case 1: Rb+ Na+ ----This ion is more strongly favored Case 2: Mg2+ ----This ion is more strongly ...
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40 views

Possible ionization and fragmentation of chemicals

Is there any generic method where I can know/calculate/generate the possible ionization and fragmentation of a specific chemical, for example, hydrogen chloride and water. Replies are greatly ...
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122 views

Vaporized sodium hydroxide?

Some time ago, I was making a $\ce{NaOH}$ solution. The solution I had made was much too concentrated, and the heat released in the dissolution of the ions caused the water to begin steaming. ...
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1answer
45 views

Reaction of sulfate ion in copper sulfate electrolysis

I am planning to try copper plating a piece of metal by performing electrolysis on an aqueous solution of copper sulfate. I plan run an electrical current with the metal I want to plate as the cathode ...
8
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3answers
262 views

Differentiation between Zn(2+), Al(3+), Mg(2+) in solution

If I have three aqueous ionic solutions in which I know that the cation is $\ce{Al^3+}$, $\ce{Mg^2+}$, or $\ce{Zn^2+}$, and that how do I find out which is which? I was thinking to add $\ce{OH-}$ in ...
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50 views

Naming ionic compounds with multiple cations and anions

I have seen complex ionic compounds that have mixed anions and/or mixed cations. For Example I have seen this: $$\ce{NaKCl2}$$ Also known as Sodium Potassium Chloride. The only information I can ...
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517 views

Really how rare are hydrogen atoms?

Hasok Chang, a chemist, but perhaps more a philosopher recently published the book Is Water H2O? . Chang used the question and an extensive web of arguments ultimately as a platform to support a ...
7
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69 views

Smoke alarm ion neutralisation

Smoke alarms are a necessary part of many modern day buildings, especially in laboratories and of course, the family home. According to the World Nuclear Association page Smoke Detectors and ...
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0answers
28 views

Debye-Huckel theory with non-polar solvents

I want to calculate the activity coefficients of mixed solvent salt solutions. I am seeing very strange behavior when I try calculating the activity coefficient of salts in non-polar solvents using ...
3
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1answer
67 views

Identify this solution

The solution is emerald green in colour. When added with water, it gives a pale blue solution When reacted with $\ce{BaCl2}$, it gives a sky blue solution and a white precipitate. When reacted with ...
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66 views

How many electrons does each shell hold?

why some times 2nd shell onward it can hold 8 electrons and other times it is like they can hold K2 L8 M18 N32? when do i have to use first method(K2 L8 M8 N8) and when to use second method (k2 L8 ...
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67 views

Quantum Numbers and Ions

How do quantum numbers change for ions? A sample question: Give the set of four quantum numbers that could represent the electron lost to form the Rb ION from the Rb atom. The answer given is n=5; ...
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1answer
62 views

What is the reason for strong acids/bases dissociating in water?

I have read that the actual definition of a strong acid is one which will fully dissociate in water, so please do not turn the problem on its head when answering. It is also my understanding that ...
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2answers
77 views

Analogies of azide?

Azide is a fairly common ion, but why aren’t there similar versions such as $\ce{P3-}$ or $\ce{B3+}$? Do they exist, is there something wrong with these ions as to make them more likely to just break ...
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1answer
48 views

How to remove nitrate from water sample?

Are there any simple methods to completely remove nitrate ions from few ml of impure water sample ? One method I am curious about is the following process : Add one or more reagents to water in ...
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0answers
22 views

Why does the molar conductivity decrease with increasing charge density?

This is a question in a problem sheet I have been set. Is it do do with the following equation: $\Lambda=\Lambda_0-a\sqrt c$? Surely charge density is proportional to concentration so therefore molar ...
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70 views

Can we picture metallic bonding as an equilibrium between electrons and cations?

Can we picture metallic bonding as an equilibrium between electrons and cations? Suppose: $$\ce{Al^3+ + 3e- <=> Al}$$
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43 views

What is more stable: a carbonate ion or a sulphate ion?

The sulphate ion has more number of resonance structures than the carbonate ion. Hence, it should be more stable than the carbonate ion. But my book says that the carbonate ion is stronger than the ...
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705 views

Can metals have a net negative charge

Normal metals like sodium or Calcium have a positive charge as $\ce{Na}^+$ or $\ce{Ca}^{2+}$. Transition metals have a loot of variable oxidation states. Yesterday I read about Iridium in Wikipedia ...
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32 views

Ionize Hydrogen and Oxygen Gas in Electrolytic Cell?

As is well known, water can be electrolyzed into oxygen and hydrogen gasses. However, all redox reactions can be run in reverse. If I were to electrolyze water in 2 closed containers (in order to trap ...
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23 views

How do you figure out the dissociation energy for ions?

Specifically $\ce{KF}$ into the $\ce{K+}$ and $\ce{F-}$ ions. I can find tables on the DE into atoms, but where would I go to find the DE between ions? I am also given that the bond length is ...
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0answers
63 views

Calculating the Molarity of an Ion?

I'm completely stuck on this one - I was doing an experiment in a lab and now I cannot find the molarity of an ion in a solution. I've looked everywhere on the web but after 2 hours of searching I ...
3
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1answer
27 views

When does a solute form ions?

If I have $\ce{HCl}$ and I put it in water, it will form ions. But, if I take $\ce{HCl}$ and put in benzene, it won't. How do you know that? If I had other substances, how would I know if it forms ...
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1k views

Is the atom the smallest particle, which takes part in chemical reactions?

According to modern atomic theory, the atom is the smallest particle which can take part in a chemical reaction. But during the formation of hydronium ion, $\ce{H+}$ ion reacts with $\ce{H2O}$ to form ...
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0answers
13 views

Separating ions in an aqueous solution [duplicate]

Let me describe a setup. You have a bucket full of water and add an appropriate amount of NaCl (common salt) in it. You wait for it to dissolve. Gradually NaCl will dissociate forming ions. Then you ...
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2answers
246 views

Why is the second reaction being neglected?

If we want to find the concentration of $\ce{H+}$ ions at equilibrium when a weak conjugate base such as $\ce{C2H3O2-}$ added to water, why do we take the conjugate base reaction for calculation i.e ...
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1answer
54 views

Why does the potential difference of a current drop, when silver nitrate is added to deionised water?

Semi-related to Why do some salt ions in solution conduct electricity better than others? After conducting more experiments, using deionised water as an analyte only, I found the potential difference ...
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155 views

Are Na and Cl ions from NaCl in water separate charged particles?

Suppose I pour some sodium chlorine into water. So, what happens is that NaCl(s) → Na+(aq) + Cl-(aq) meaning that the ionic bond between Na and Cl breaks up (correct this far?) Now, does this mean ...
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61 views

Why Ca 2+ and not Ca +2

I have been learning chemistry for a year or two but I still can't understand this. According to maths we should place the plus or minus sign in front of a number like -2. However, In chemistry we ...
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1answer
57 views

Does the speed of an ion affect the current that can flow through a solution?

Typically, when a cathode and anode are inserted into a solution that allows current to flow, the ions are moving with a certain kinetic energy. If the ions were to gain kinetic energy (through ...
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1answer
180 views

Why do some salt ions in solution conduct electricity better than others?

My experiment involves a potentiometric titration, and I have used $\ce{AgNO3}$ as a titrant and KCl/KI/deionised water only as an analyte. In the image below of my data, the potential difference as ...
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1answer
120 views

What is the total concentration (in mol dm−3) of ions in each of the following solutions, assuming complete dissociation

$0.750\ \mathrm{mol\ dm^{-3}}$ solution of $\ce{K2CO3}$ (I believe is $2.25\ \mathrm{mol\ dm^{-3}}$) $0.355\ \mathrm{mol\ dm^{-3}}$ solution of $\ce{AlCl3}$ (I believe is $1.42\ \mathrm{mol\ ...
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1answer
53 views

Ion-selective electrodes

Some ion-selective electrodes can be expensive (starting from $500). Is there any relatively inexpensive do-it-yourself alternatives that would still give very accurate results? How does one make an ...
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1answer
49 views

Iodine ion vs caesium ion size

An iodine ion is the larger of the two, but why if they have the same amount of electrons? Also, $\ce{Li}$ is larger than $\ce{Li+}$, don't more electrons mean larger radius?
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2answers
77 views

What is the OH in alcohol?

What is the $\ce{OH}$ functional group in alcohol (ethanol)? My teacher told me it isn't the same as the $\ce{OH-}$ ion or hydroxide. But it does donate one electron to the respective carbon chain and ...
4
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2answers
127 views

Why does Cobalt have different coordination numbers in its complexes with water and thiocyanate?

I'd like to know why does cobalt(II), $\ce{Co^2+}$, form $\ce{[Co(H2O)6]^2+}$ complex with water while it forms $\ce{[Co(SCN)4]^2-}$ with the thiocyanate? Why is there $\ce{6H2O}$ but only $\ce{4 ...
2
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1answer
66 views

Why should the redox reaction happen between the copper ions and iron atoms?

I know that when $Cu$$^+$$^2$ ions react to $Fe$ atoms, it becomes $Cu$ + $Fe$$^+$$^2$. My question is, why? Copper atoms normally have 29 electrons. These means that in the K-shell there are 2 ...
6
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2answers
280 views

Wade's rules for Zintl ions

How do you apply Wade's rules to Zintl polyhedral cluster anions ? For example, I believe $[\ce{Bi_3}]^{3-}$ is a triangle. My approach to justify would be: 5 electrons per each Bi atom 3 electrons ...
2
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1answer
49 views

How do I convert zwitterions to neutral form in Avogadro?

I'd like to be able to convert zwitterions to neutral form in Avogadro if possible. How do I do this?
2
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1answer
84 views

Why does the ionic product of water remain constant after addition of non-neutral solute?

In my textbook, it is given that the ionic product of water $K_w$ remains constant even when a non-neutral solute such as an acid is added to it. $$K_w=\ce{[H3+O][OH- ]}$$ When a strong acid is added ...
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2answers
150 views

Acidity of oxonium ion

How was the pKa value (-1.7) for the oxonium ion determined? Why does it correspond to the minimum pH value accessible in water? What reaction does it represent?
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1answer
46 views

Comparing Basic strengths of different species

Well I was doing questions on organic chemistry.I came across tonnes of questions where I was required to compare basic and acidic strengths. Comparing acidic strengths is fine - I remove an ...
8
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1answer
238 views

Negative ions and health: pseudo science or something more?

Over the last year or so I've heard from friends, who subscribe to holistic medicine, talk about negative ions, saying that they are good for your mental/physical health. Being the only one among them ...
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1answer
113 views

How is tea affecting water's color?

Black tea is an amazing product of the green tea leaves. A recent study has proven that; The anion profile for the tea solution indicated that oxalate and citrate were the major anions detected. ...
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1answer
351 views

How is the dissolution of acetic acid that makes its aqueous solution a poor electrolyte?

I'm having a difficulty understanding the following quote from Wikipedia - Dissociation: Acetic acid is extremely soluble in water, but most of the compound dissolves into molecules, rendering it ...
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2answers
92 views

Hydrogen peroxide from water

Is it possible that $\ce{2 OH-}$ from water could react to form $\ce{H2O2}$? I mean most autoionization forms $\ce{H3O+}$ and $\ce{OH-}$. However I think it is possible that $\ce{H-}$ and $\ce{OH+}$ ...
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69 views

What kind of carbon ions exist?

I think there are $\ce{C^{4-}}$ and $\ce{C^{2-}}$ existing. How can we find the charge of ions in the elements? Should we look at the group or valence?
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94 views

Where does the Fe(III) ion go?

Iron(II) sulphate solution is added to a test-tube. Following this, potassium manganate solution is added gradually to the test-tube as well. The observation seen is that the green solution turns pink ...
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234 views

Does Iron (III) Sulfate react with copper?

As my understanding, there should be an oxidation-reduction reaction: $$ \ce{2Fe^{3+} + Cu \rightarrow 2Fe^{2+} + Cu^{2+}} $$ However, I always see the process using $\ce{FeCl_3}$ to etch ...
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1answer
52 views

Why they have different flame colour?

At school, I learnt about the metal and their flame colour. Here's my observations. $\ce{K^+}$- Lavender $\ce{Ba^2+}$- Yellow-Green $\ce{Ca^2+}$- Yellow-Red $\ce{Li^+}$- Flame Red $\ce{Na^+}$- ...