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When I place a straw in carbontated drink and blow (making bubbling noises), more gas bubbles rise to the surface. The gas bubbles which rise to the surface are from the carbon dioxide gas dissolved in the drink, I'm not talking about the air bubbles I made with the straw?
Why does this happen? |
As far as I know, for all substances other than helium, if you extrapolate the solid-gas line on the phase diagram, it passes through the origin. That is, no matter how low the temperature is, you can still vaporize the substance by lowering the pressure, and no matter how low the pressure is, you can still freeze the ... |
Is helium-4 a liquid at zero temperature and zero pressure? |
- Name of the compund: **Dimethyl nitroxide**
- Lewis structure:
![enter image description here][3]
- The properly way to determine the Lewis structure, based on this example, is:
1. Total valence electrons: $4\cdot2 + 5 + 6 + 1\cdot6 = 25$
2. Total electrons needed for octets/doublets: $8\cdot4+2\cdot6... |
As far as I know, for all substances other than helium, if you extrapolate the solid-gas line on the phase diagram, it passes through the origin. That is, no matter how low the temperature is, you can still vaporize the substance by lowering the pressure, and no matter how low the pressure is, you can still freeze the ... |
A greater positive charge means the ligand is strongly attracted and pulled closer, and thus it creates a stronger crystal field. The potential energy value of the barycentre should thus be higher, since repulsion experienced by the d electrons is stronger. Why is though the value of the Δo increased - the potential en... |
Why does the value of Δo increase with increased charge on the metal? |
The boiling point of ammonia is -33$^\circ$C while that of HCN is 25$^\circ$C. In a recent AP Chemistry test, a free response question asked why this is the case. Can someone shine light on this? |
The enthalpy of vaporization of [HCN][1] is higher than for [NH$_3$][2], which suggest that HCN molecules interact more strongly than NH$_3$ molecules. C-H bonds are not usually considered good hydrogen bond donors, but HCN is unusual. For example HCN has a [pK$_a$ value of 9.2][3], indicating that it is a reasonably ... |
The boiling point of ammonia is -33$^\circ$C while that of $\ce{HCN}$ is 25$^\circ$C. In a recent AP Chemistry test, a free response question asked why this is the case. Can someone shine light on this? |
The boiling point of ammonia is −33 °C while that of $\ce{HCN}$ is 25 °C. In a recent AP Chemistry test, a free response question asked why this is the case. Can someone shine light on this? |
Supporting Jan's answer, actually: Consider the points below from the book [Hydrogen Bonding: A Theoretical Perspective][1], p. 102.
"Moreover, the hydrogen in HCN is acidic enough that the molecule may act as an effective proton donor... When paired with NH$_3$, HCN acts as a proton donor..." <br>
This agrees with... |
In many sites I see that they take $\ce{C}$ with valence 4, bur our teacher takes it with valence 2. With what valence should I take $\ce{C}$? |
What is the Lewis Structure for CO? |
My professor gave my class a set of practice questions for the mid-term. One of those questions asks for the molar mass of a number of chemicals, such as lithium bromide and silver nitrate. We haven't studied those chemicals, so there's little reason for the professor to expect us to have memorized the elements that co... |
Does the term 'silver nitrate' express all of its constituent chemical elements? |
My professor gave my class a set of practice questions for the mid-term. One of those questions asks for the molar mass of a number of chemicals, such as lithium bromide and silver nitrate. We haven't studied those chemicals, so there's little reason for the professor to expect us to have memorized the elements that co... |
In many sites, I see that they put $\ce{O}$ in the middle, but our teacher said that we should put $\ce{O}$ near the extremity. Which is the best way? |
What is the Lewis Structure for HClO? |
Just getting interested in this stuff.
People are saying I should crystallize salt, for example. What things could I do instead of salt with and still get a crystal from? Thanks a ton!! |
Often crystal structures found online from past published crystallography experiments are of the **salt** of a molecule of biologic interest, as opposed to the freebase form of the molecule itself. For example, I have a CIF file for mescaline hydrobromide ([CCDC 1211316][1]) at the moment that I would like to create a ... |
How would one construct a 3D model of a molecule based on the crystal structure of its salts? |
Fish oil, is susposed to suffer from rancidity(i.e. oxidation) when stored improperly , for example in hot temperature.
I'm interested in buying fish oil from abroad(usa) it will be shipped by air and won't be kept in a cold chain,i live in a mediternean nation(climate wise).
How should i choose my fish oil , ... |
Choosing fish-oil that won't oxidize in long travel ? |
Our teacher told us this trick to tell if complex is going to be square planar.
We are considering the fact that the coordination no. is 4.
If the metal has a $\ce{d^7}$, $\ce{d^8}$ or $\ce{d^9}$ configuration along with a **strong field ligand** or $\ce{d^4}$ with **weak field ligand** then complex will be s... |
Could a dissolving metal in nh3 reduction of an organic compound still proceed if a metal such as aluminium were used instead of sodium? I'm not sure about the aluminium amine or amide structure that would be formed . |
On the table published here ([link][1]) each cell has one to five numerals arranged vertically in its top right corner. The sum of those numbers is always the relative atomic mass of the element. I suspect that, in most cases, two of those numerals represent the number of protons and the number of neutrons, respectivel... |
What do the numerals on the top right corner of the cells in the periodic table represent? |
In particular, how do a methylene more (in the case of the pentane) and a methylene less (in the case of the octane) make the difference in harmfulness in comparation with, respectively, the butane and the nonane? |
What makes pentane, hexane, heptane, and octane dangerous, while butane and nonane aren't? |
Is there a way to cheaply transfer (plunge by pushing) a viscous liquid in to another container without plunger-to-tube discharge? |
Could reduction of an organic compound by reacting it with sodium dissolved in $\ce{NH3}$ still proceed if a metal such as aluminium were used instead of sodium? I'm not sure about the aluminium amine or amide structure that would be formed. |
What is the entropy change when 1.00 mol of ideal gas that raises reversibly from 10 C to 50 C at constant pressure, constant volume, assuming the heat capacity is independent from temperature? |
What is the entropy change when 1.00 mol of ideal gas that raises reversibly from 10 C to 50 C at constant pressure, constant volume, assuming the heat capacity is independent from temperature?
This is all the information given. I m assuming that the formula delta S = C ln (T2/T1), however, I do not know how the heat ... |
What is the entropy change when 1.00 mol of ideal gas that raises reversibly from 10 °C to 50 °C at constant pressure, constant volume, assuming the heat capacity is independent from temperature?
This is all the information given. I m assuming that the formula $\Delta S = C \ln (T_2/T_1)$, however, I do not know how... |
What is the entropy change when 1.00 mol of ideal gas that raises reversibly from 10 °C to 50 °C at constant pressure, constant volume, assuming the heat capacity is independent from temperature?
This is all the information given. I m assuming that the formula $\Delta S = C \ln (T_2/T_1)$ is used. However, I do not ... |
If Ferric Chloride was added to a water sample which had calcium bicarbonate alkalinity present, would the reaction be a 'stoichiometry reaction' or a 'limting reagent reaction'?
For example, if 1g of Ferric Chloride was added, how much precipitate would form [Fe(OH)3] and what type of reaction (mentioned above) wou... |
If ferric chloride was added to a water sample which had calcium bicarbonate alkalinity present, would the reaction be a 'stoichiometry reaction' or a 'limting reagent reaction'?
For example, if 1g of ferric chloride was added, how much precipitate would form [$\ce{Fe(OH)3}$] and what type of reaction (mentioned abo... |
If ferric chloride was added to a water sample which had calcium bicarbonate alkalinity present, would the reaction be a 'stoichiometry reaction' or a 'limting reagent reaction'?
For example, if 1g of ferric chloride was added, how much precipitate would form [$\ce{Fe(OH)2}$] and what type of reaction (mentioned abo... |
If ferric chloride was added to a water sample which had calcium bicarbonate alkalinity present, would the reaction be a 'stoichiometry reaction' or a 'limting reagent reaction'?
For example, if 1g of ferric chloride was added, how much precipitate would form [$\ce{Fe(OH)3}$] and what type of reaction (mentioned abo... |
The Gattermann-Koch Reation involves the formation of an aryl aldehyde using carbon monoxide and hydrochloric acid as reactants. The reaction is catalyzed by Aluminum Tri-Chloride in the presence of trace amounts of Cuprous Chloride.
![enter image description here][1]
What I don't understand about this reaction is th... |
The delocalized electrons in a metal move about because of the electrostatic attractions between them and many different positive ion cores. But why does the same not occur with the ion cores themselves? Why are electrons, which bear the same charge as nuclei, mobile, while the nuclei themselves are not? |
Why do ion cores not move in a metal? |
The delocalized electrons in a metal move about because of the electrostatic attractions between them and many different positive ion cores. But why does the same not occur with the ion cores themselves? Why are electrons, which bear the same magnitude of charge as nuclei, mobile, while the nuclei themselves are not? |
You have outlined that the **formyl cloride** is generated as the reactive, electrophilic intermediate under these conditions.
You are planning to perform an electrophilic aromatic substitution, but in a phenol, there's high electron density on the $\ce{O}$ atom. Isn't it conceivable that your main reaction product ... |
i have had two types of urea fertiliser analysed,the results are as follows,
46n(46% nitrogen)-which is sold as a urea fertiliser tests at 46.1 ureic nitrogen
38n 19s(38%nitrogen,19%sulphur)-which i understand to contain ammonium sulphate and urea-tests at 33% nitric nitrogen and 7.4% ammoniacal nitrogen
my qu... |
This user absolutely insists that when a chloride ion is present in water (for example, when NaCl dissolves in water) that Cl- ion is ionically bound to the hydrogen atom:
http://biology.stackexchange.com/questions/34449/why-do-i-smell-chlorine-when-my-sinuses-are-clogged?noredirect=1#comment55324_34449
I then in... |
Does water ionically bond to chloride ion? |
I had a fairly simple question regarding supersaturation and crystallization. When a supersaturated solution is crystallized, is *all* of the solute crystallized or just the excess solute (such that the solution remains saturated)? After crystallization, would you expect to find some quantity of the solute still dissol... |
As water is a polar molecule, as per the UC Davis ChemWiki page [All About Water][1], shown below:
![enter image description here][2]
The caption reads:
> the positive and negative charges are not distributed uniformly. This is illustrated by the gradation in color in the schematic diagram here. The electronic (... |
As water is a polar molecule, as per the UC Davis ChemWiki page [All About Water][1], shown below:
![enter image description here][2]
The caption reads:
> the positive and negative charges are not distributed uniformly. This is illustrated by the gradation in color in the schematic diagram here. The electronic (... |
I have had two types of urea fertiliser analysed, the results are as follows:
$\ce{46N}$ (46% nitrogen) - which is sold as a urea fertiliser, tests at 46.1% ureic nitrogen.
$\ce{38N}$ $\ce{19S}$ (38% nitrogen, 19% sulphur) - which I understand to contain ammonium sulphate and urea, tests at 33% nitric nitrogen an... |
This user absolutely insists that when a chloride ion is present in water (for example, when $\ce{NaCl}$ dissolves in water) that $\ce{Cl-}$ ion is ionically bound to the hydrogen atom:
http://biology.stackexchange.com/questions/34449/why-do-i-smell-chlorine-when-my-sinuses-are-clogged?noredirect=1#comment55324_3444... |
The most common mechanism for when $\ce{NaCl}$ dissolves is as folows:
As water is a polar molecule, as per the UC Davis ChemWiki page [All About Water][1], shown below:
![enter image description here][2]
The caption reads:
> the positive and negative charges are not distributed uniformly. This is illustrated... |
If ferric chloride was added to a water sample which had calcium bicarbonate alkalinity present, would the reaction be a ‘stoichiometry reaction’ or a ‘limiting reagent reaction’?
For example, if 1 g of ferric chloride was added, how much precipitate would form [$\ce{Fe(OH)3}$] and what type of reaction (mentioned a... |
The mechanism of the olefine metathesis using Grubbs' catalyst consists of many [2+2] cycloadditions and reverse cycloadditions. How are they in accordance with the Woodward-Hoffmann rules? I think that there are two (4q+2)s components and that's not an odd number. Are these metathesis photochemical? |
Context:
AP Chem student popping my StackExchange cherry. Am giving presentation over Coenzyme Q10 Wednesday for my final project, but we haven't studied any biochem this year. So questions have arisen.
CoQ10 has a Quinone head, an isoprenyl tail, and these additional oxygens on the left and three methyl groups... |
Name of these parts in CoQ10? |
In E2 reaction there are more than one product. Accoring to Zaitsev's rule - ""The alkene formed in greatest amount is the one that corresponds to removal of the hydrogen from the β-carbon having the fewest hydrogen substituents."(wikipedia)
Now, my question is, how can the base effect the percentage of the minor and ... |
In E2 reaction there are more than one product. Accoring to Zaitsev's rule - "The alkene formed in greatest amount is the one that corresponds to removal of the hydrogen from the β-carbon having the fewest hydrogen substituents." (Wikipedia)
Now, my question is, how can the base effect the percentage of the minor an... |
Will a reaction(E2) that has 2 potential product go faster than a reaction that has 3 potential products? |
**Note**-I've already answered this question. All I want to know is if my reasoning is correct.
**Case 1:**
Rb<sup>+</sup>
Na<sup>+</sup> ----**This ion is more strongly favored**
**Case 2:**
Mg<sup>2+</sup> ----**This ion is more strongly favored**
Na<sup>+</sup>
**Reasoning:**
For the first ca... |
Explain why these ions are more strongly hydrated in an aqueous solution? |
In E2 reaction, there is more than one product. According to Zaitsev’s rule – “The alkene formed in greatest amount is the one that corresponds to removal of the hydrogen from the β-carbon having the fewest hydrogen substituents.” (Wikipedia)
Now, my question is, how can the base effect the percentage of the minor a... |
Will a reaction(E2) that has 2 potential product go faster than a reaction that has 3 potential products?
**specific information** - the moleculas in the pictures are each reacting with methanol. I figured it's an E2 reaction (I hope I'm right) and the question is which one will go faster?![enter image description he... |
Will a reaction(E2) that has 2 potential product go faster than a reaction that has 3 potential products?
**specific information** - the molecules in the pictures are each reacting with methanol. I figured it's an E2 reaction (I hope I'm right) and the question is which one will go faster?![enter image description he... |
The mechanism of the olefine metathesis using Grubbs' catalyst consists of many [2+2] cycloadditions and reverse cycloadditions. How are they in accordance with the Woodward-Hoffmann rules? I think that there are two (4q+2)s components and that's not an odd number. |
How do you know the number of ligands surrounding the metal ion?
for e.g Ni 2+ ion in NH3 solution,the complex ion is written as [Ni(NH3)6]2+ but Cu2+ in NH3 solution it is [Cu(NH3)4]2+.
So how do you guess the number for different metal ions like Ag2+? |
My teacher said that Flourine is more electro-negtive than oxygen thus it will take electrons of oxygen.
But now, why won't other Group 17 elements, like Chlorine, Bromine, Iodine, would take electrons from oxygen? They too have just 7 electrons on their valence shells.
Technically they should but yet they have ... |
Why any other element except flourine wouldn't take electrons from oxygen? |
Is it possible for an atom to combine with 8 other elements of same or other type? If yes, then please give some examples. If no, then what could be the possible reason for it? |
Can an atom join with more than 8 other atoms? |
In the ene-yne metathesis how to know which product will form predominately, as the mechanisms to both are plausible?
![enter image description here][1]
[1]: https://i.stack.imgur.com/fLrlr.gif |
Is it possible for an atom to combine with 8 other elements of same or other type? If yes, then please give some examples. If no, then what could be the possible reason for it?
Update + Edit: My question is not about valence shell electrons. My question is about whether an x element could combine with other more tha... |
As the question suggests I am wondering the **difference** between standard electrode potentials and standard reduction potentials. I know that they are **both a measure of the Voltage** from certain reactions, and can be used to calculate the **feasibility** of a reaction - but when do you use which / what is the diff... |
What is the Difference between difference between Standard Electrode Potentials and Standard Reduction Potentials? |
Am giving presentation over Coenzyme Q10 Wednesday for my final project, but we haven't studied any biochem this year. So questions have arisen.
CoQ10 has a Quinone head, an isoprenyl tail, and these additional oxygens on the left and three methyl groups not a part of the Quinone head or tail.
Is there a name ... |
To the best of my knowledge, energy equals work, $\mathrm{E = W}$; work equals force multiplied by distance, $\mathrm{W = Fm}$ ; force equals mass multiplied by acceleration, $\mathrm{F = MA}$; and acceleration equals distance per second squared, $\mathrm{A = m \setminus s^2}$. However, when I substitute those values ... |
When I heat up a balloon, does the air inside the balloon increase in pressure as well as volume? I thought pressure and volume were inversely proportional? Or does pressure and volume increase as temperature increases? Thanks. |
When I heat up a balloon, does the air inside increase in pressure as well as volume? I though pressure and volume were inversely proportional? |
When I heat up a balloon, does the air inside increase in pressure as well as volume? |
**14 coordination** is claimed in $\ce{U(BH4)4}$ ([ref_1][1], p. 268). The molecule exists as a polymer in the solid state. Six hydrogens from two of the $\ce{BH4}$ groups bond between the boron and uranium (a bridge bond). Two hydrogens from each of the two remaining $\ce{BH4}$ groups also bridge bond to uranium; t... |
How do you know the number of ligands surrounding the metal ion?
for e.g $\ce{Ni^2+}$ ion in $\ce{NH3}$ solution,the complex ion is written as $\ce{[Ni(NH3)6]^2+}$ but $\ce{Cu^2+}$ in $\ce{NH3}$ solution it is $\ce{[Cu(NH3)4]^2+}$.
So how do you guess the number for different metal ions like $\ce{Ag^2+}$? |
Is it possible for an atom to bond with 8 other elements (same or other type)? If yes, then please give some examples. If no, then what could be the possible reason for it?
Update + Edit: My question is not about valence shell electrons. My question is about whether an element could combine with more than 8 other *s... |
Can an atom bond with more than 8 other atoms? |
I believe your reasoning is correct (more or less). Solvation is influenced by charge to size ratios. Higher the charge to size ratio, the easier it is for the species to be solvated by water molecules.
Apply this idea to both your cases. (note: in the second case, I don't get your argument about molar mass. The id... |
Regarding chemical synergies I read: If someone ingests various products containing sodium benzoate (for example soft drinks that exist) AND if one has had some quantity of vitamin C there might be 'reactions' that produce benzene, a carcinogen.
Some people have told me you'd have to drink a lot of pop for this to ... |
Regarding chemical synergies, I read: if someone ingests various products containing sodium benzoate (for example soft drinks that exist) AND if one has had some quantity of vitamin C there might be 'reactions' that produce benzene, a carcinogen.
Some people have told me you'd have to drink a lot of pop for this to ... |
How do you know the number of ligands surrounding the metal ion?
_e.g._ the obtained complex of $\ce{Ni^2+}$ ion in $\ce{NH3}$ solution is written as $\ce{[Ni(NH3)6]^2+}$ but $\ce{Cu^2+}$ in $\ce{NH3}$ solution is $\ce{[Cu(NH3)4]^2+}$.
So how do you guess the number for different metal ions like $\ce{Ag^2+}$? |
How do you know the number of ligands surrounding a metal ion?
_e.g._ the obtained complex of $\ce{Ni^2+}$ ion in $\ce{NH3}$ solution is written as $\ce{[Ni(NH3)6]^2+}$ but $\ce{Cu^2+}$ in $\ce{NH3}$ solution is $\ce{[Cu(NH3)4]^2+}$.
So how do you find the number for different metal ions like $\ce{Ag^2+}$? |
Sodium benzoate in soft drinks reacting to produce benzene? |
Why is mercury the only metal that is liquid at room temperature?
Note: I am a high school student and would appreciate an answer, if possible, suited for my level of understanding.
Thank you. |
Why is mercury liquid? |
My textbook frequently mentions:
$sp^3$ hybrid orbital has 25% $s$-character and 75% $p$-character.
My question is: what are these "character"? |
My teacher said that fluorine is more electronegative than oxygen thus it will take electrons of oxygen.
But now, why won't other Group 17 elements, like chlorine, bromine, iodine, would take electrons from oxygen? They too have just 7 electrons in their valence shells.
Technically, they should but yet they have... |
Why any other element except fluorine wouldn't take electrons from oxygen? |
Superheated water is achieved by heating water above 100 degree Celsius under high pressure.
Now, suppose the temperature at which the water is getting heated is around 250 Celsius and sufficient pressure is provided. If, I now make a hole in the container, the pressure will decrease obviously, but what will happen... |
Difference between superheated steam and superheated water? |
Superheated water is achieved by heating water above 100 degree Celsius under high pressure.
Now, suppose the temperature at which the water is getting heated is around 250 Celsius and sufficient pressure is provided. If, I now make a small-hole in the container, the pressure will decrease obviously, but what will ... |
What happens if I make a hole in the superheated water's conatiner? |
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