26
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If I drink water without sipping, is there a chance of saliva diffusing into my bottle?
This question reminds me of a germaphobic classmate I had back in Middle-school. He would always stay clear of public lavatories/urinals because he was under the impression that urinating at one would ...
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23
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Could ammonium azanide exist?
Technically, ordinary liquid ammonia may be regarded as a very dilute solution of ammonium azanide through its autoionization. (Water is similarly very dilute hydronium hydroxide.)
This technicality ...
- 61.1k
22
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The impossibility of 100% ionic bond
A "100% ionic" bond would be a bond whose bonding electron(s) were never in the vicinity of the cation, but rather always in unperturbed valence orbitals of the anion. That's not far from the truth ...
- 1,170
20
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Are salts (e.g. NaCl) soluble in liquid metals?
Yes, to varying extent. So just as a starter for your bibliographic research:
The solubility of salts in metals, a technical report by the US Department of Energy turned in by December 31st, 1960:
&...
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19
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How can FeS2 be the formula of iron sulphide and CaC2 be the formula of calcium carbide?
What you call iron sulphide, in my opinion, is more appropriately referred to as or iron disulphide.
If one were to assign oxidation states to each atom, an appropriate description would be $\ce{Fe^...
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16
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Effect of noble gas configuration on polarising power
Recall the fact that the basic difference between an ionic bond and a covalent bond, is basically just charge separation. In ionic bonds, charges are well separated, and the bond arises due to ...
16
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What is the analogue of "molecule" for ionic compounds?
The term you are looking for is formula unit, I think. Wikipedia doesn't really describe it super well, but just to give an example, you could write the sentence
$\pu{58.44 g}$ of $\ce{NaCl}$ ...
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16
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Are all ionic compounds salts?
Interestingly, IUPAC states that a "salt" is "a chemical compound consisting of an assembly of cations and anions". Under this definition, all ionic compounds are salts, and all salts are ionic ...
- 29.1k
14
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How do you explain the formula Fe3O4 using the ionic compound theory?
Iron forms both $\ce{Fe^2+}$ and $\ce{Fe^3+}$ ions. The first combine with oxygen ions to $\ce{FeO}$; the second $\ce{Fe2O3}$.
$\ce{Fe3O4}$ can be thought of as a mixture of both compounds in equal ...
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Which has higher lattice energy: MgO or LiF?
$\ce {MgO}$ ($\approx 3800$ $\pu{kJ mol^{-1}}$) has higher lattice energy than $\ce {LiF}$ ($\approx 1045$ $\pu{kJ mol^{-1}}$) mainly because of the greater charge on $\ce{Mg^2^{+}}$ ion and $\ce {O^{...
- 5,511
14
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The impossibility of 100% ionic bond
Actually bonds that are $100\%$ ionic, or close to it, are possible. But they require a little ingenuity. Instead of combining atoms of very different electronegativity, we can build multiatomic ...
- 61.1k
13
votes
Accepted
Why is MnO2 not a peroxide?
Peroxides contain two oxygens connected by a single bond. X-ray or neutron diffraction will show that the oxygens in $\ce{MnO2}$ are too far apart to be bonded, and therefore it is not a peroxide.
...
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13
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Why is MnO2 not a peroxide?
The question’s logical premise is skewed. $\ce{CO2}$ is carbon(IV) oxide or carbon dioxide. But carbon(II) also exists and so does carbon(II) oxide (carbon monoxide, $\ce{CO}$). Just because there are ...
- 68.5k
13
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Covalent and Ionic Bonds
Bonds are usually used to describe how electrons are shared. "Partially ionic bonds" are polar covalent bonds. Which is not the same as saying that a compound has different types of bonds in the whole ...
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13
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Which has a greater dominance: hydration enthalpy or lattice energy?
The dominant factor depends on situation to situation.Here is an explanation i found helpful while predicting solubilities
The hydration energy is of Form A÷r1 + B÷r2 .
The lattice energy is of form ...
- 450
13
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Is calcium chloride an acidic or basic salt?
Calcium hydroxide has solubility about 1.9 g/L. This is enough to create pH above 11, i.e. a strongly basic solution.
$\ce{CaCl2}$ solutions should be very slightly acidic if they were made from pure ...
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13
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Are salts (e.g. NaCl) soluble in liquid metals?
The solubility of oxygen, in effect cuprous oxide, in molten copper is important in the smelting and processing of this metal.
Silvain et al. 1 give the copper-oxygen phase diagram below:
Thus at $\...
- 61.1k
12
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How can FeS2 be the formula of iron sulphide and CaC2 be the formula of calcium carbide?
There is no point in doubting the composition of these compounds, the measurements don't lie. ;-)
The point is that S or C (or e.g. P) can not only form bonds to the metal, but also between ...
- 12.2k
12
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If I drink water without sipping, is there a chance of saliva diffusing into my bottle?
With respect to the exact question in a highly literal sense, it is highly unlikely and next to impossible for ions to diffuse upstream in this manner; the linked question deals with this very nicely.
...
11
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Is beryllium difluoride covalent or ionic?
There is a very relevant article by Gillespie Covalent and Ionic Molecules: Why Are BeF2 and AlF3 High Melting Point Solids whereas BF3 and SiF4 Are Gases? J. Chem. Educ., 1998, 75 (7), p 923.
...
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11
votes
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How is NH4Cl a salt?
This is not the correct definition of salt. The IUPAC definition of salt is "a chemical compound consisting of an assembly of cations and anions". In fact there are many salts which do not fit the ...
- 1,246
11
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An ionic compound dissociates into 3 ions of 3 different elements?
Yup, they are definitely possible. Such salts are called as mixed salts. They furnish more than two ions when dissolved in water. A popular example is Mohr's salt, popularly used as a standard titrant ...
11
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Is tropylium cyclopentadienide possible?
While I can't give a definitive disproof, my intuition is that an unsubstituted cyclopentadienide anion would be far too nucleophilic and react with the tropylium cation at non-cryogenic temperatures (...
- 29.1k
11
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Could ammonium azanide exist?
In standard conditions ammonium amide in pure form wouldn't be stable as it would turn into ammonia through proton transfer.
However, it is being taught that in liquid ammonia there is an equilibrium ...
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10
votes
The impossibility of 100% ionic bond
In a "100 %" covalent bond, like the $\sigma_{ss}$ bond in the dihydrogen molecule, the electron probability density is perfectly symmetrically divided between the two bonded nuclei because both have ...
- 1,927
10
votes
Does lithium form ionic hydride?
As described in the comments, there really is no sharp boundary between "ionic" and "covalent" bonding. With metal hydrides the situation is muddled further because the usual ...
- 61.1k
10
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Are salts (e.g. NaCl) soluble in liquid metals?
Bredig et.al. did an extensive study on the miscibility of liquid metals with salts especially alkali metal-alkali metal halide system. Later Dworkin et.al. worked together with M.A. Bredig and ...
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9
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If I mix carbon dioxide and sodium hydroxide in the right amounts in water, do I get baking soda?
This is certainly one method by which sodium bicarbonate can be produced. According to this Wikipedia article:
$\ce{NaHCO3}$ may be obtained by the reaction of carbon dioxide with an aqueous ...
- 17.6k
9
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Why does adding salt to water reduce the pH?
This is probably an effect in which sodium ions from the salt are being weakly detected by the glass electrode, giving the appearance of a lower pH. Try add the same concentration of salt to samples ...
- 9,352
9
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Is it possible to freeze water by dissolving a salt?
It is possible, in a significantly different way that you envision. Freezing point depression via the cryoscopic constant is an example of a colligative property, which holds only for relatively ...
- 29.1k
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