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I, being of sound constitution and with firm belief in the coulomb barrier, find palladium's absorption of hydrogen fascinating.
If I understand correctly, H2 in the presence of Pd readily dissociates as it dissolves into the metal. With the dissociation energy for the H-H bond being so large, how is this possible... |
What is the significance of enclosing marks in chemical names in determining the uniqueness of a substance (organic and inorganic)?
Can a simple change in the type of enclosing mark used indicate that we are dealing with a different substance or does it just mean that the names were written slightly differently (or ... |
What is the biggest issue with using methane (CH4) as a combustable fuel? |
What's the greatest issue with using methane as a combustable fuel? |
What's the greatest drawback with using methane as a combustable fuel? |
I understand that oxidation numbers are a method for keeping track of electrons in a reaction and how they are generally assigned (electrons in a bond are assigned to the more electronegative atom).
My question, however, is: why does this method work? Why does assigning these arbitrary numbers based on electronegati... |
Why do oxidation numbers work? |
If I understand correctly, H2 in the presence of Pd readily dissociates as it dissolves into the metal. With the dissociation energy for the H-H bond being so large, how is this possible?
At first I thought that the H atoms were falling to a lower energy level in the Pd that was somehow only available if they were ... |
If I understand correctly, H<sub>2</sub> in the presence of Pd readily dissociates as it dissolves into the metal. With the dissociation energy for the H-H bond being so large, how is this possible?
At first I thought that the H atoms were falling to a lower energy level in the Pd that was somehow only available if... |
How does Palladium dissociate H2 so easily? |
From what point of view? Environmental? Industrial? Practical?
In Europe (I live in Italy) we use methane a lot, both for automotive and for house heating/cooking.
From the environmental point ov view, CH4 is one of the best choices (toghether with LPG). When burnt (both in termodynamics engines and in free-flame... |
The output from an anerobic kitchen waste digester is mostly CH4, and CO2.
If the methane is collected over water; algae/moss may use the CO2 to grow. Yet Oxygen is released ... which, together with methane, is a potent environment.
Will the oxygen, in this closed jar filled with water+algae+moss, recombine to for... |
Is it possible to prevent methane combining with oxygen? |
Can someone draw the reaction that leads to the generation of HOCl when [dichloroisocyanuric acid][1] (structure shown below) is dissolved in water?
![enter image description here][2]
[1]: http://en.wikipedia.org/wiki/Dichloroisocyanuric_acid
[2]: https://i.stack.imgur.com/lpkyc.png |
>Will the oxygen, in this closed jar filled with water+algae+moss, recombine to form CO2 and H2O?
Very slowly, you will not see this. However, it is much worse, as explosive composition of $CH_4$ and $O_2$ will form.
In industrial applications it is possible to separate $CO_2$ from $CH_4$ and them move $CO_2$ ... |
Why are crystals of Naphthalene needle-shaped after sublimation? |
I wonder why crystals of Naphthalene are needle-shaped after sublimation. Googling the fact, I could only confirm that it is true but failed to find the reason. Could someone please shed some light as to why this happens? |
Why does Naphthalene turn into needle-shaped crystals by sublimation? |
When hypochlorous acid is dissolved in water, is it the chlorine atom or the oxygen that serves as the anti microbial agent? |
Has diatomic oxygen ever been observed in a 3- oxidation state, i.e. $O_2^{3-}$? Have any ab intio calculations been done on this ion? |
O2 in a 3- oxidation state? |
How do you know if a polymer is a thermoset or a thermoplastic? For example:
- hydroxybutanoic acid
- 2-amino-3- hydroxybutanoic acid
(I am not sure if these are correct in English)
I know what thermosets and thermoplastics are, and their properties, but I don't know how to see if polymers of a certain m... |
A thermoset or a thermoplastic? |
When hydrocarbons burn with little oxygen, carbon is produced. What form do these particulates of carbon come in?
Is it a simple molecule like $S_8$, or a small fragment of a larger structure, like graphite?
Why is this form more stable than others?
|
If I understand correctly, H<sub>2</sub> in the presence of Pd readily dissociates as it dissolves into the metal. With the dissociation energy for the H-H bond being so large, how is this possible?
At first I thought that the H atoms were falling to a lower energy level in the Pd that was somehow only available if... |
How does Palladium dissociate H₂ so easily? |
I understand that oxidation numbers are a method for keeping track of electrons in a reaction and how they are generally assigned (electrons in a bond are assigned to the more electronegative atom).
Why does this method work? Why does assigning these arbitrary numbers based on electronegativity work in predicting an... |
I don't understand how to find the volume in this problem..
A flask containing 63.2 mL of neon gas was collected over water at 21C and 788 mm Hg. What is this volume of gas at STP? (WVP at 21C = 18.6 mm Hg) |
Why water can't mix with oil or cooking oil (both saturated and unsaturated)? |
Why water can't mix with oil or cooking oil? |
Has diatomic oxygen ever been observed with a 3- charge, i.e. $O_2^{3-}$? Have any ab intio calculations been done on this ion? |
The textbook answer for why water can't mix with oil is to use the rule 'like dissolves like'. But a rule in science is none other than summarizing a few collected facts. Answering a question with a rule is like pointing a single fact - why water can't mix with oil - to a collection of facts instead. This easily invite... |
Like evaporation happens only on the surface of a liquid, and boiling/vapourisation takes place throughout the body, how does sublimation occur? and why? |
Does sublimation happen only on the surface or throughout the body? |
How do you Synthesise a Fatty Acid Amide? |
Like evaporation happens only on the surface of a liquid, and boiling/vapourisation takes place throughout the body, how does sublimation occur? Why? |
How does one synthesise 2-monoglycerides from triglycerides with additional ingredients if necessary?
My first instinct would be to add a catalyst for the reaction of triglyceride (composed of 3 fatty acids and one glycerol bonded)->3 fatty acids + glycerol (for instance, sodium hydroxide) and then add additional gl... |
How does one synthesise 2-Monoglycerides from Triglycerides? |
My teacher in physics course attributed this effect to phonons but I am skeptical about this argument, it feels like he is overlooking the whole question -- what about with Silica that has similar structure to diamond with covalent bonds? My friend attributed this to small mass of atoms and large Hooke constant, consid... |
Classical reason for good heat conductance in diamond? |
My teacher in physics course attributed this effect to phonons but I am skeptical about this argument, it feels like he is overlooking the whole question -- what about with Silica that has similar structure to diamond with covalent bonds?
My friend attributed this to small mass of atoms and large Young constant, co... |
My teacher in my physics course attributed this effect to phonons but I am skeptical about this argument, it feels like he is overlooking the whole question -- what about with Silica that has similar structure to diamond with covalent bonds?
My friend attributed this to the small mass of atoms and large Young const... |
I am trying to understand the synthesis of nitrocellulose.
A mixture of sulfuric acid and nitric acid is used to nitrate cellulose. The sulfuric acid acts as a catalyst, producing NO<sub>2</sub><sup>+</sup> ions from the nitric acid which bind at certain sites on the cellulose chain to nitrate it. So nitrate salts can... |
>The sulfuric acid acts by protonating nitric acid to yield nitronium and hydronium ions.
Electrophilic nitration reactions like the production of nitrocellulose require sulfuric acid because of the dehydrative properties of sulfuric acid. Sulfuric acid is a non-nucleophilic acid - all it can do is mediate proton t... |
>Some background, since most readers would probably need it.
A [thermoplastic][1] is a polymer that becomes pliable/moldable upon heating, and then returns to a solid (keeping its new shape) when cooled. Thermoplastics are generally high molecular weight polymers with very few or no crosslinks. Polymer chains are he... |
>The sulfuric acid acts by protonating nitric acid to yield nitronium and hydronium ions.
Electrophilic nitration reactions like the production of nitrocellulose require sulfuric acid because of the dehydrative properties of sulfuric acid. Sulfuric acid is a non-nucleophilic acid - all it can do is mediate proton t... |
The situation is akin to boiling. If a molecule at the surface frees itself of its attractions to its neighbors, it can move into the vapor phase easily. Same thing with evaporation at the surface of a solid.
Can a molecule evaporate from the bulk liquid? The answer is no. Imagine such a thing happening. The es... |
How do you synthesise a fatty acid amide? |
I was given a question as follows:
> If the following gasses are to mix, what is the partial pressure of the *Ne* gas?
>
> https://i.stack.imgur.com/8Pn7w.png
The correct answer is **0.1**. I cannot figure out how my professor derived this equation. From the ideal gas law, all I can arrive to is this:
$P_x =... |
How to derive partial gas equation? |
I am trying to understand the synthesis of nitrocellulose.
A mixture of sulfuric acid and nitric acid is used to nitrate cellulose. The sulfuric acid acts as a catalyst, producing NO<sub>2</sub><sup>+</sup> ions from the nitric acid which bind at certain sites on the cellulose chain to nitrate it. So nitrate salts can... |
I was given a question as follows:
> If the following gasses are to mix, what is the partial pressure of the *Ne* gas?
>
> ![https://i.stack.imgur.com/8Pn7w.png][1]
The correct answer is **0.1**. I cannot figure out how my professor derived this equation. From the ideal gas law, all I can arrive to is this:
... |
The total pressure of the system is:
$\frac{1.0\times0.5+1.0\times0.4+2.0\times0.2}{1.0+1.0+2.0}=1.3/4=0.325$
i.e. just the sum of the $PV$s divided by the sum of the $V$s. Then $0.325$ is the sum of the partial pressures by the Law of Partial Pressures. So this at least suggest that the individual partial pres... |
How do you Synthesise a Fatty Acid Amide? |
So during school today, I am running an electrolysis experiment with water and sodium bicarbonate copper leads on both the anode and cathode. I am noticing the usual $NaO$ on the anode, and $H_{2}C_{2}$ on the cathode. However, on the anode, the copper is obviously oxidizing, and changing the hue of the water to a br... |
First of all: sorry world about my english, it's weak, but for me the only way to improve it's make mistakes and study. I hope Shakespeare isn't turning over in his grave.
I'm trying to make rocket fuel by Hydrazyne and hydrogen peroxide with home products my question is: Is there any way to sintetize hidrazyne with... |
First of all: sorry world about my english, it's weak, but for me the only way to improve it's make mistakes and study. I hope Shakespeare isn't turning over in his grave.
I'm trying to make rocket fuel by Hydrazyne and hydrogen peroxide with home products my question is: Is there any way to sintetize hidrazyne with... |
I'm trying to make rocket fuel by hydrazine and hydrogen peroxide with home products my question is: Is there any way to synthesize hydrazine with bleach and ammonia? using $\ce{H2SO4}$ as a catalyst. I wanna put an action man in orbit!.
Thanks in advance!
|
I'm trying to make rocket fuel by hydrazine and hydrogen peroxide with home products my question is: Is there any way to synthesize hydrazine with bleach and ammonia, using $\ce{H2SO4}$ as a catalyst? I wanna put an action figure in orbit.
Thanks in advance!
|
> Is there any way to synthesize hydrazine with bleach and ammonia?
**Do not do this.**
My answer is not "yes" or "no". My answer is **Don't**. Do not try this without proper safety equipment and training, and then think twice or three times before doing so, and then have an ambulance standing by. Certainly don'... |
I sympathize with your desire to launch an action figure. However, the chemistry you propose is really dangerous. You would be better off with black-powder based rockets.
> Is there any way to synthesize hydrazine with bleach and ammonia?
**Do not do this.**
My answer is not "yes" or "no". My answer is **Don'... |
There are many incorrect things in your question and your answer. I will deal with the misconceptions. Then, I provide my own answer below.
>Sodium compounds:
$\ce{Na2C2}$ is sodium carbide. It reacts violently with water. $\ce{Na2CO3}$ is sodium carbonate. $\ce{NaO}$ is not a valid formula for any of the oxides ... |
Let's say you have a solution that is vinegar and it has salt (NaCl) dissolved in it. Then you place old dull pennies in it. Then you look at it 5 minutes later and the pennies are clean and new looking again.
Why is the salt necessary for this process and what exactly does it do? |
Let's say you have a solution that is vinegar and it has salt ($NaCl$) dissolved in it. Then you place old dull pennies in it. Then you look at it 5 minutes later and the pennies are clean and looking like new again.
Why is the salt necessary for this process and what exactly does it do? |
Let's say you have a solution that is vinegar and it has salt ($\ce{NaCl}$) dissolved in it. Then you place old dull pennies in it. Then you look at it 5 minutes later and the pennies are clean and looking like new again.
Why is the salt necessary for this process and what exactly does it do? |
I want to put an action figure in orbit but I need some Know-How about make a secure (the most secured posible), no too much expensive rocket fuel engine. The design of the engine (very primitive... depends on this).
I've read some information about hydrazine and peroxid hydrogen but is too damm dangerous to use and... |
I want to put an action figure in orbit but I need to know how to make a secure yet not too expensive rocket fuel engine. The design of the engine must very primitive and not too complicated.
I've read some information about hydrazine and hydrogen-peroxide but it is too dangerous to use and make at a non-commercial... |
Why are the energy levels for vibrational energy in a molecule discrete as opposed to continuous?
I don't understand how a vibration can't have continuous amounts of energy that depend on the frequency of any infrared photon.
Can someone combine this question onto my stack exchange account: olly_price, because I ca... |
Why are there quantised energy levels in the vibrational energy of a molecule? |
>Sodium compounds:
$\ce{Na2C2}$ is sodium carbide. It reacts violently with water. $\ce{Na2CO3}$ is sodium carbonate. $\ce{NaO}$ is not a valid formula for any of the oxides of sodium: $\ce{Na2O},\ \ce{Na2O2},$ and $\ce{NaO2}$ are all real compounds, and they all react with water to produce $\ce{NaOH}$, which is pro... |
So I understand molecular orbitals and how to do VSEPR models, but I seem to be struggling with understanding localized bonding theory and how to do hybridizations. After drawing the initial lewis structure then molecular orbital, I do not know where to go in terms of whether something has a Pi or Sigma bond. Also, h... |
"Why" is a good question, and one that science has yet to fully answer. We generally have a good understanding of "how" things work at the subatomic level, based on over a century of observation followed by theory and math backed up by experimentation. However, the really basic, naively simple questions, like "where do... |
"Why" is a good question, and one that science has yet to fully answer. We generally have a good understanding of "how" things work at the subatomic level, based on over a century of observation followed by theory and math backed up by experimentation. However, the really basic, naively simple questions, like "where do... |
During a reaction if addition on one of the $\pi$ bonds of an allene(containing even number of $\pi$ bonds like $\ce {H2C=C=CH2}$) takes place then a carbocation is formed. To decide the position of the positive charge, we look at the stability of the carbocation.
---
Example:
$$\ce {H2C=C=CH2 ->[\ce{H3O+}]} \quad... |
What are the common names of this two types of plastic? |
I need to create a container which hold ~150 to 500 ml water. My plan is to create something like a inverse cone. I will apply pressure (~20psi) on the top of the cone and I want to create a hole at and only at the tip of the cone.
I plan to make the tip of the cone thinner, so that it will be easier to be break. ... |
Which plastic can be partially broken by pressure easily? |
The chemical disinfection (inactivation of bacteria) in fresh water can occur through a number of mechanisms, including oxidation of cell walls, inactivation of key enzymes and disruption of nucleic acids, thereby rendering them non-functional.
Chlorine was first used as a disinfectant in the USA in 1908 (slightly ... |
Disinfection by redox reaction using ozone gas $(O_{3})$, a fast and powerful oxisizing agent, is typically used to reduces or eliminates the toxicity caused by residual chlorine. Oxygen gas $(O_{2})$ on the other hand is a much weaker oxidizing agent than hypochlorous acid.
![Oxidation power][1]
Hypochlorous aci... |
Hypochlorous acid $(HOCl)$ dissociates in water to $H^{+}$ and hypochlorite ion $(OCl^{-})$.
$HOCl\leftrightarrow H^{+} + OCl^{-}$
Because hypochlorous acid $(HOCl)$ is uncharged, it is better able to penetrate cell walls than other chlorine species and is about **80 times** more effective than hypochlorite $(OCl... |
The chemical disinfection (inactivation of bacteria) in fresh water can occur through a number of mechanisms, including oxidation of cell walls, inactivation of key enzymes and disruption of nucleic acids, thereby rendering them non-functional.
When chlorine was first used as a disinfectant in the USA in 1908 (slig... |
The chemical disinfection (inactivation of bacteria) in fresh water can occur through a number of mechanisms, including oxidation of cell walls, inactivation of key enzymes and disruption of nucleic acids, thereby rendering them non-functional. The precise mechanism of inactivation depends upon the nature of micro-orga... |
The chemical disinfection (inactivation of bacteria) in fresh water can occur through a number of mechanisms, including oxidation of cell walls, inactivation of key enzymes and disruption of nucleic acids, thereby rendering them non-functional. The precise mechanism of inactivation depends upon the nature of micro-orga... |
Which materials or compounds expand in response to cold temperatures?
This material or compound should expand at a slow (but constant rate), from about 0-20 months when in the following temperature range -10 to -25°C. Also, the compound should not react with plastic or be toxic to humans or environment.
Please expl... |
Which materials/compounds expand in response to cold temperatures? |
During a reaction if addition on one of the $\pi$ bonds of an allene(containing even number of $\pi$ bonds like $\ce {H2C=C=CH2}$) takes place then a carbocation is formed. To decide the position of the positive charge, we look at the stability of the carbocation.
---
Example:
$$\ce {H2C=C=CH2 ->[\ce{H3O+}]} \quad... |
How does one synthesise 2-monoglycerides from triglycerides with additional ingredients if necessary?
My first instinct would be to add a catalyst for the reaction of $triglyceride \rightarrow 3 FA + glycerol$ (FA=fatty acid; for instance a catalyst could be sodium hydroxide) and then add additional glycerol so as t... |
Relative atomic masses of atoms of all chemical elements are numbers without unit, being the value of proportion compared to the 1/12 mass of the carbon atom.
But the relative atomic mass of carbon is never 12! Instead, it's 12.01 or finer, 12.011.
How come? |
Relative atomic masses of atoms of all chemical elements are numbers without units, being the value of proportion compared to $\frac{1}{12}^\text{th}$ the mass of the carbon atom.
But the relative atomic mass of carbon is never 12! Instead, it is 12.01 or, more accurately, 12.011.
Why is this so? |
My teacher in my physics course attributed this effect to phonons, more [here](http://physics.stackexchange.com/questions/45910/why-do-phonons-cause-excellent-heat-conduction-in-diamonds), but I am skeptical about this argument, it feels like he is overlooking the whole question -- what about with Silica that has simil... |
I have been researching for a Physics/Chemistry exam and thought; what will the future periods in the periodic table (periods 8 and above) would entail? Each block contains its own properties that allow for accurate predictions of elements in these blocks. Each block has very unique properties and benefits society in m... |
What are the g-block's predicted properties? |
I have been researching for a Physics/Chemistry exam and thought; what will the future periods in the periodic table (periods 8 and above) would entail? Each block contains its own properties that allow for accurate predictions of elements in these blocks. Each block has very unique properties and benefits society in m... |
"Why" is a good question, and one that science has yet to fully answer. We generally have a good understanding of "how" things work at the subatomic level, based on over a century of observation followed by theory and math backed up by experimentation. However, the really basic, naively simple questions, like "where do... |
"Why" is a good question, and one that science has yet to fully answer. We generally have a good understanding of "how" things work at the subatomic level, based on over a century of observation followed by theory and math backed up by experimentation. However, the really basic, naively simple questions, like "where do... |
"Why" is a good question, and one that science has yet to fully answer. We generally have a good understanding of "how" things work at the subatomic level, based on over a century of observation followed by theory and math backed up by experimentation. However, the really basic, naively simple questions, like "where do... |
The answer to your question might need a few clarifying points. My answer will mostly focus on the protonation (and deprotonation) of allene based on gas-phase experiments and theoretical calculations. A few references that point to elements that will be used concerning the allyl and 2-propenyl cations are as follow : ... |
Is there any excel table for elements properties? |
Where can I find a downloadable spreadsheet of element properties? |
Well, here's a CSV file that I parsed out of the JSON data provided by [Paul Nathan's website][1], which in turn was produced from [gPeriodic][2] data in response to [this question][3]. gPeriodic is FOSS, so I can only assume that the element data contained within is good to share, though I have no idea of its provenan... |
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