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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60 views

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

$\text{0.750mol}~ \text{dm}^{-3}$ Solution of $\ce{K2CO3}$ (I believe is $\text{2.25mol dm}^{-3}$) $\text{0.355mol dm}^{-3}$ solution of $\ce{AlCl3}$ (I believe is $\text{1.42mol dm}^{-3}$) Does ...
4
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0answers
25 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 ...
2
votes
1answer
22 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?
-1
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2answers
47 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
74 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
votes
1answer
27 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
votes
2answers
182 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
34 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
36 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 ...
2
votes
1answer
35 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?
1
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1answer
33 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 ...
7
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1answer
86 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 ...
2
votes
1answer
60 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. ...
0
votes
1answer
51 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 ...
-1
votes
2answers
75 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 $\ce{OH+}$ ...
-1
votes
1answer
59 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?
3
votes
2answers
74 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 ...
4
votes
1answer
40 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 ...
0
votes
1answer
38 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 $\ce{Na^+}$- ...
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0answers
27 views

How to determine relative size of polyatomic ions?

How would you determine the size of a polyatomic ion? For example when determining which ion is bigger, NH2- or I-, what would you use to determine the size difference? I know that I- would be much ...
3
votes
1answer
73 views

Why is the hydride ion negative?

Recently, I saw a video about sodium hydride and it saw it was made up with $\ce{Na+}$ ions and $\ce{H-}$ ions. My problem is: aren't all hydrogen ions positive? And in what conditions can $\ce{H-}$ ...
0
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2answers
43 views

What is the bonding picture in Peroxomonosulfate?

In $\ce{SO5^{2-}}$, can somebody tell me which orbitals are used to form the pi bonds in this anion. Please tell the hybridization. And the lewis structure. Well I tried and the answers I got was sp3 ...
0
votes
1answer
22 views

number of ions present from moles

I have $0.0585$ moles of $\ce{Al^{3+}}$, and need to find the number of actual ions. I thought I just divided by $6.022\times 10^{23}$ but I get $9.7\times 10^{-26}$, and the book says it should be ...
4
votes
2answers
81 views

Should I use H3O+ or H+?

I learned the equation $$\ce{H2O + H+ -> H3O+}$$ And I know $\ce{H^+}$ and $\ce{H_3O+}$ are the same. But I am confused as to when can I use $\ce{H^+}$ and $\ce{H_3O+}$?
0
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1answer
65 views

How would you find the mass in grams, if you only know the number of particles of a portion of the formula?

If you were given a question like below: What is the mass in grams of a sample of $\ce{Fe2(SO4)3}$ that contains $3.59 \times 10^{23}$ sulfate ions, $\ce{SO4^{2−}}$ ? The molar mass of ...
2
votes
1answer
32 views

How thermochromism happen?

I learned that when $PbO$ is hot, it is orange. When $PbO$ is cold, it is yellow. I know this's called thermochromism. But how do that happen? Is it because the ions inside doing something?
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1answer
46 views

What is the difference between carboxylate ions and groups?

I would like to know the difference between carboxylate ions carboxyl groups? An example is is $\ce{COOH}$ and $\ce{COO}$.
3
votes
1answer
32 views

Why do strong acids dissociate (almost) fully on a molecular level?

In the Brønsted-Lowry theory, strong acids $\ce{HA}$ dissociate using water and react into hydronium ions and the conjugate bases $\ce{A-}$. However I never understood in the strong acids case what ...
5
votes
2answers
103 views

Why the salts in a salt bridge?

Take the example of a copper and zinc galvanic cell, connected by a salt bridge of $\ce{KNO3}$. I understand how the reactions will result in positive and negative charges, and that the ions of the ...
0
votes
1answer
52 views

What happens when oxidizing Ni(OH)2 with a strong base?

In an aqueous solution, Nickel oxyhydroxide is oxidised with a 1:1 ratio of aqueous Sodium hydroxide. My goal is to produce Nickel oxyhydroxide ($\ce{NiOOH}$). Strong Base: $\ce{NaOH + H2O ...
0
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0answers
46 views

Why is the sodium +1 ion larger than the neon atom?

Why is the sodium +1 ion larger than the neon atom? The removal of the electron from sodium should cause the ion to be the same size as the neon atom.
1
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1answer
172 views

How does a limiting reactant relate to the concentration of ions in solution?

Given the question A sample of 1.50 g of lead(II) nitrate is mixed with 125 mL of 0.100 M sodium sulfate solution. What is the limiting reactant in the reaction? Calculate the concentrations of ...
0
votes
1answer
77 views

Structures of Thiosulfate, Dithionate & Tetrathionate Ions [closed]

I am trying to find the structures of thiosulfate, Dithionate & Tetrathionate Ions but I am not getting an exact answer. Please help.
3
votes
1answer
24 views

A metal Q forms a carbonate and a nitrate. What is the molecular formula of the nitrate of Q?

Good day. This is my first post in any chemistry site. A metal $\ce{Q}$ forms a carbonate and a nitrate. The molecular formula of the carbonate of $\ce{Q}$ is $\ce{QCO3}$. What is the molecular ...
0
votes
1answer
167 views

Why has lithium bromide a slight solubility in organic solvents?

Why has lithium bromide a slight solubility in organic solvents? Theoretical, LiBr is an ionic compounds, so it should be only soluble in polar solvent like water. But why is it soluble in others?
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0answers
26 views

Kinetics of the conversion from metal oxide to metal hydroxide in water

How long can a metal oxide such as magnesium oxide remain in solution before being converted to the metal hydroxide?
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4answers
2k views

Why does salt dissolved in water taste like salt? If it's just Na+ and Cl- ions

When NaCl is dissolved into water it breaks down into Na+ and Cl-. It stays in this form until the water evaporates and then the ions go back to normal NaCl. So why does water with salt in it still ...
3
votes
1answer
97 views

Proton affinities in machine readable format?

Short: How to get proton affinities for a large list of chemicals? A database? A programming API? Longer: I have ca. 2000 chemicals (downloaded from MCM, mostly organics that occur in the atmosphere ...
1
vote
1answer
53 views

Potassium Atom can act as reducing agent, yet ion cannot?

I am currently looking through a revision sheet, however it has caught me on a question 'Explain why a potassium atom can act as a reducing agent yet a potassium ion cannot'. I have done brief ...
4
votes
1answer
64 views

Unknown anion (one carbon and two nitrogen atoms, charge 2-)

What's the name of this ion: $\ce{CN_2^{2-}}$? I think that it has this structure: $\ce{{}^{-}N=C=N^{-}}$.
2
votes
1answer
87 views

Net ionic equation with only aqueous ions

When you turn a balanced equation into a net ionic equation, you ignore all the ions that are spectator ions (aqueous on one side as well as the other). You only write the solid and the aqueous ions ...
0
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1answer
27 views

Chemical nomenclature of ions

I'm a very beginner in chemistry. The book I'm studying says that an ion is an atom, or a collection of atoms, that has an electric charge, then it writes about the difference between molecules and ...
3
votes
2answers
68 views

Why does water break salt really

A kid asked me this question just the other day, and I said that the positive part of $\ce{H2O}$ attracts the negative $\ce{Cl}$ ion and the negative part of the $\ce{H2O}$ attracts the positive Na ...
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2answers
34 views

Can citric acid protonation produce benzene and water

Is this reaction possible: $\ce{C6H8O7 + 12 H3O -> C6H6 + 19 H2O}$? Considering that the $\ce{H+}$ can be induced by ionization of the citric acid solution the benzene can be produced in this way?
8
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1answer
222 views

Explaining Ionization to kids

I have a quest to explain a physical, chemical theory to kids of age 8-12. The topic is "Ionization". We all understand from early experiments of Physics and Chemistry (the Millikan oil drop ...
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0answers
50 views

Is Oxide Anion more stable than O^+

O likes to be negative if charged at all. Most metal oxides are of the form $\ce{A^{x+} O^{2-}_{x/2}}$ (where $x$ is the magnitude of the positive charge and $\ce{A}$ is a metal.) Here, despite the ...
1
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1answer
30 views

Balancing ionic equations and determining number of ions

There were two questions that I've listed below that I've had troubles on. I got an answer in both, but both of them weren't correct. For the first question, they list the answer to be D and then ...
0
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3answers
56 views

Why cellphone batteries are still bad?

There are constantly new features in cellphones over the years, but it seems like batteries are not getting any better. Why is that?
4
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1answer
140 views

Why Aren't Chlorides Of The Noble Gases As Prevalent As Their Fluorides?

I can't find the answer to this question on this SE website, and I apologize for the repetition if it has been answered before. It is my understanding that compound formation has only been observed ...
3
votes
1answer
967 views

Is there an easy way to remember charges on ions?

I have a chemistry test coming up and I might need to know the charge that goes with the different ions like $\ce{SO4}$ has $-2$, $\ce{NO2}$ is $-1$ and $\ce{PO4}$ is $-3$. Is there an easy way to ...