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After a lot of digging around, I finally found something about this in J.D. Lee's Concise Inorganic Chemistry. I thought I'd post whatever I found over here anyway since it's very interesting:
Answer to question 2
Complex formation by Lanthanides is different from that of Actinides. In Lanthanides, the $4f$ orbit... |
I don't think a combination also can be called a "state" i.e. that the chemical state of vapour or solid would be just a combination. When I read wikioedia about "chemical state" it refers to just a combination. But AFAIK, an entity that has just combination does not have a state. So how do we know what is a state and ... |
What is the difference between a chemical state and just a combination? |
I don't think a combination also can be called a "state" i.e. that the chemical state of vapour or solid would be just a combination. When I read Wikipedia about "chemical state" it refers to just a combination. But AFAIK, an entity that has just combination does not have a state. So how do we know what is a state and ... |
What type of voltmeter are you using? to verify the answer to my question, you need to determine 1) the [precision][1] and 2) the [detection limit][2] of the instrument .
The precision is a measure of the error in a typical measurement. The smaller the standard deviation in repeat measurements, the higher the precis... |
$\ce{CaF2}$ is insoluble in water, but $\ce{CaCl2}$, $\ce{CaBr2}$, $\ce{CaI2}$ are soluble. Why is this so? |
Question:
> Suggest an explanation for the coordination number in the $\ce{CsCl}$ lattice being different from those in $\ce{NaCl}$.
Standard answer:
> Caesium ion is larger than sodium ion, hence it can be surrounded by greater number of chloride ions.
My questions:
- The question didn’t specify whe... |
In this video, Steve Spangler says the substance he is using (a polyethylene oxide): http://www.youtube.com/watch?v=MzsORE0ae10&NR=1&feature=endscreen
He mentions that one molecule would go to the moon and back twice! I have a hard time believing this, but I guess it must be true.. Is it? |
How long can polyethylene molecules be? |
Lithography: Is isopropanol a developer and/or a stopper? |
I'm dealing with electrochemistry problems.
For the following reaction
$$2H^+ + 2e^- \leftrightarrow H_2 \ \ \ \ \ \ \ E^o= 0 \ V$$
Does it make sense to say
$$\Delta G^o=-nFE^o = 0 $$
Which would mean the reaction is in equilibrium?
|
Why is it that dry erase markers allow permanent markings to come off?
Demonstration: http://www.youtube.com/watch?v=GD-MJ-nF55M |
Why does permanent marker writing come off a white board when coated with white board marker? |
When we plot molecular orbital diagrams we use a linear combination of atomic orbitals.
Where can I find the energies of particular atomic orbitals?
In the picture below, the energies of 2s and 2p orbitals of Oxygen are lower than Carbon's 2s and 2p orbitals of Carbon, what is the logic behind this?
![Molecul... |
In this video, Steve Spangler says the substance he is using (a polyethylene oxide): http://www.youtube.com/watch?v=m-88M75_PCI
He mentions that one molecule would go to the moon and back twice! I have a hard time believing this, but I guess it must be true.. Is it true that polyethylene molecules can be that long? |
Short answer? Possibly, but these ones aren't.
So, the other thing mentioned in the video is that the specific material he's using has a molecular weight of approximately four million. If we assume it's ordinary poly-ethylene oxide, we can get the rough number of $\ce{(CH2)2O}$ subunits by just dividing by the molec... |
This is a complex issue, particularly because people often like to think in terms of an indepedent-particle picture (i.e. the aufbau filling up orbitals), even though the exact many-body wavefunction has strong electron-electron correlations. So let me rephrase your question:
What is the relationship between the KS ... |
Is it possible to produce graphene out of air? |
I've bought a white powder. Label on the package states that the powder contains sodium chloride, potassium chloride and potassium citrate. How to make sure that the powder does contain potassium chloride? Mainly interested in the presence of potassium ions |
I know the reaction proceeds as follows:
Pyruvate accepts the electrons from NADH to form lactate. What would be the intermediate in this reaction? Would it be NADH or NAD+? |
What metabolite intermediate will accumulate in a mammalian cell-free extracts capable of glycolysis if lactate dehydrogenase is inhibited? |
For the papal election, white and black smoke are going to be used to signal success or failure in the voting process.
As far as I understood from several sources, the ballots are burnt and chemicals are added to create the color.
But what chemicals are used to get black or white smoke? |
What chemicals are going to be used to make the smoke black or white? |
I've bought a white powder. The label on the package states that the powder contains sodium chloride, potassium chloride and potassium citrate. How can I make sure that the powder does indeed contain potassium chloride? I'm mainly interested in the presence of potassium ions. |
According to the biogenic theory of hydrocarbon formation, hydrocarbons come from pressurized carbohydrates.
I am looking for an explanation of what happens to the oxygen in the process. How could the oxygen break away from the hydroxyl groups of molecules like glucose to form hydrocarbons? |
What happens to the oxygen when carbohydrates turn into hydrocarbons? |
I think [Titanium Tetrachloride] would be a good option for white smoke (I've heard it's used quite often in smoke bombs). But it releases quite a lot of $HCl$ gas and so it might not be very safe.
A quick Google search comes up with a lot of answers to your question though. This site even answers your question in ... |
- What do you want?
If you're just looking for a source of potassium ions you could just buy KCl or some other compound, they're relatively cheap if not pro analysis. If you actually want to test for K+:
- What else do you know about the product?
Tests are completely different for different amounts of K+. Doe... |
- What do you want?
If you're just looking for a source of potassium ions you could just buy KCl or some other compound, they're relatively cheap if not pro analysis. If you actually want to test for K+:
- What else do you know about the product?
Tests are completely different for different amounts of K+. Doe... |
- What do you want?
If you're just looking for a source of potassium ions you could just buy KCl or some other compound, they're relatively cheap if not pro analysis. If you actually want to test for K+:
- What else do you know about the product?
Tests are completely different for different amounts of K+. Doe... |
- What do you want?
If you're just looking for a source of potassium ions you could just buy KCl or some other compound, they're relatively cheap if not pro analysis. If you actually want to test for K+:
- What else do you know about the product?
Tests are completely different for different amounts of K+. Doe... |
Last week I was discussing with a friend how we thought the stripeless cleaning of windows is achieved when using a cleaner like Windex Glass Cleaner as opposed to just using hot water, in which case you do get stripes left behind.
At first we thought that the stripeless nature was caused by surfactants in the clea... |
I'm doing an experiment where I'm measuring the effect of changing the Cu2+ ion concentration on the voltage in a copper-zinc galvanic cell. I'll be doing at least five trials for five concentration I'm testing(from 0.2-1.0M), so in total that is 25 trials. However, do I need a new piece of filter paper as a salt bridg... |
What is the procedure of designing a salt bridge for a galvanic cell? |
Last week I was discussing with a friend how we thought the stripeless cleaning of windows is achieved when using a cleaner like Windex Glass Cleaner as opposed to just using hot water, in which case you do get stripes left behind.
At first we thought that the stripeless nature was caused by surfactants in the clea... |
I'm doing an experiment where I'm measuring the effect of changing the $\ce{Cu^{2+}}$ ion concentration on the voltage in a copper-zinc galvanic cell.
I'll be doing at least five trials for each of the five concentrations I'm testing for (from $0.2-1.0\:\mathrm{M}$), so in total that is 25 trials. However, do I nee... |
I'm looking for a wet-etchant to remove aluminum oxide, but not etch unoxidized metal (with > 10:1 selectivity)
I know about chromium(IV) oxide and fluorine-based etchants, but those are problematic for safety and disposal. Are there other etchants? Can be acid or base.
The aluminum oxide was created by anodizing... |
I'm looking for a wet-etchant to remove aluminum oxide, but not etch the unoxidized metal (with greater than 10:1 selectivity)
I know about chromium(IV) oxide and fluorine-based etchants, but those are problematic for safety and disposal. Are there other etchants? It can be an acid or a base.
The aluminum oxide w... |
What is the correct name for a reaction like this?
$$ \ce{ 4MnO2 ->[500^\circ c] 2Mn2O3 + O2 ^}$$
Is it a synthesis, or a Decomposition?
I tried to find it out with http://en.wikipedia.org/wiki/Chemical_reaction but i did not get the link between the formula and the nomenclature as it seems to be both. |
What is the correct name for a reaction like this?
$$ \ce{ 4MnO2 ->[500\ ^\circ \text{C}] 2Mn2O3 + O2 ^}$$
Is it a synthesis, or a Decomposition?
I tried to find it out with http://en.wikipedia.org/wiki/Chemical_reaction but i did not get the link between the formula and the nomenclature as it seems to be both. |
What is the best method for calculating partial charges and protonation/deprotonation states of a small molecule such as phenol or caffeine, depending on the pH? For instance, it is well known that above pH=10 or so phenol is deprotonated, but there is data about its protonation around pH=2. For more complex molecules ... |
I was given the first structure, and then drew the other 5 resonance structures.
![enter image description here][1]
First of all, are they correct? ChemBioDraw had some complaints, but as far as I can see there's the same amount of electrons, and no valence orbitals exceeding capacity.
My reasoning is that t... |
> First of all, are they correct? ChemBioDraw had some complaints, but as far as I can see there's the same amount of electrons, and no valence orbitals exceeding capacity.
**Yes**, these are the six most important resonance structures for this compound. The reason ChemDraw complains is that it is trying to act smar... |
in the text i'm reading it is stated that :-
<blockquote>
As the molecular mass increases in any homologous series, a gradation in physical properties is seen. This is because the melting points and boiling points increase with increasing molecular mass. Other physical properties such as solubility in a particular ... |
In the text that I'm reading it is stated that :
>As the molecular mass increases in any homologous series, a gradation in physical properties is seen. This is because the melting points and boiling points increase with increasing molecular mass. Other physical properties such as solubility in a particular solvent a... |
> My question is regarding the last line, what kind of gradation in solubiltiy is observed? Increase or decrease?
**Both**
Solubility is not one single property, but a collection of related properties. Solubility in water is different from solubility in ethanol, which is different from solubility in benzene.
... |
I'm doing exercises on hybridisation, and I was given this molecule (this is the facit):
![enter image description here][1]
I'm wondering about this (electron deficient) oxygen atom. My intuition says it should be ${sp^2}$ like the facit says, but honestly I only see that it's $sp$ hybridised. Is it because you ... |
Why is this atom SP2 hybridised? |
should chemical formula of ethanol be written as CH<sub>3</sub>CH<sub>2</sub>OH or C<sub>2</sub>H<sub>5</sub>OH ? And whats the logic behind it? I have seen the former being used more often, so why is ethane represented by C<sub>2</sub>H<sub>6</sub> than CH<sub>3</sub>CH<sub>3</sub>? |
I'm learning how to apply the VSEPR theory to Lewis structures and in my homework I'm being asked to provide the hybridization of the central atom in each Lewis structure I've drawn.
I've drawn out the Lewis structure for all the required compounds and figured out the arrangements of the electron regions, and figure... |
How do I figure out the hybridization of a particular atom in a molecule? |
If you can assign the total electron geometry (geometry of all electron domains, not just bonding domains) on the central atom using VSEPR, then you can always automatically assign hybridization. Hybridization was invented to make quantum mechanical bonding theories work better with known empirical geometries. If you k... |
The melting and boiling point of Lithium as compared to other members of the Alkali group metals is high. But, Lithium does not occur in free state.
So, what does it mean that it has high melting and boiling point? How is its b.p and m.p measured if its not in free state? |
What is the best way to learn Chemical properties, physical properties and peculiar behaviour of metals in inorganic chemistry?
It is very hard to learn all of these for each group. |
The melting and boiling point of Lithium as compared to other members of the Alkali group metals is high. But, Lithium does not occur in the free state.
So, what does it mean that it has high melting and boiling point? How are its BP and MP measured if it isn't in the free state? |
Will borosilicate glass absorb 808nm laser light? If it instead refracts, then what is the refractive index? Also, will borosilicate reflect lower frequencies of light like those used in non contact temp. measurements? |
Will borosilicate glass absorb 808nm laser light? |
I was wondering if there was a difference between Keq and Kc. I think they both refer to the Equilibrium Constant. If I'm wrong, could you please tell me the difference between the two? Thanks! |
Is At a non metal or a metalloid?
A metalloid is an element which exhibits some of the properties of a metal as well as those of a non metal. |
Is At a non metal or a metalloid? |
This is a screenshot of a portion of a metal organic framework (MOF). These are two oxygens of two [NMP][1] solvent molecules. What I am wondering is why they are so close and overlapping like this. I checked the CIF file, and occupancy for all atoms in this structure is 1, so it doesn't seem to be the case that th... |
Overlapping oxygens in crystal structure -- what's going on? |
I was wondering if there was a difference between $K_{eq}$ and $K_c$. I think they both refer to the Equilibrium Constant. If I'm wrong, could you please tell me the difference between the two? Thanks! |
Is Astatine a non metal or a metalloid?
A metalloid is an element which exhibits some of the properties of a metal as well as those of a non metal. |
Ketones are relatively much harder to oxidise, but they do undergo oxidation reactions at extreme temperatures. Our teacher also told us about the popoff's rule which says that during oxidation of unsymmetrical ketones, the >C=O group remains with the smaller of the two alky groups.. Could you please give me a hint as... |
>Is Astatine a non metal or a metalloid?
**Unknown**
According to the Wikipedia article on [astatine][1], the longest-lived isotope has a half-life of 8.1 hours. The element is so radioactive that large samples would melt and vaporize under the heat generated by its own radioactivity. Such behavior makes it diffi... |
Titanium is expensive, although it is not rare and titanium dioxide is a ubiquitous component, it's part of such mundane articles as toothpaste, paper or plastics.
The reason for that is that the processes that extract titanium from titanium dioxide (which occurs naturally and just needs some inexpensive purificatio... |
Why is it hard to reduce titanium dioxide? |
I was trying to know what is the probability for the carbon atoms to rotate .I know that in double bond it is 0 % and I think it is 100 % in single bond but how about the triple bond ? |
I was trying to know what is the probability for the carbon atoms to rotate .I know that in single bond it is 0 % and I think it is 100 % in double bond but how about the triple bond ? |
How can I reconcile all of the chemical properties, physical properties and peculiar behaviour of metals in inorganic chemistry for the purposes of studying these systematically?
It is very hard to learn all of these for each group. |
Why are intramolecular Hydrogen bonds weaker than intermolecular hydrogen bonds ?
The question is itself in the main topic.
Thanks in advance... :) |
Why are intramolecular Hydrogen bonds weaker than intermolecular hydrogen bonds? |
What method was used to solve the quantum 3-Body Problem? I heard it was solved and was not sure about the status of the problem. |
How was the quantum 3-Body problem solved? |
A question in my chemistry textbook gives me a list of formulas for molecules and ions and then asks me to determine (using molecular orbital theory) whether or not each would exist in a relatively stable form.
How can I tell this? The chapter covers molecular shapes, valence bond theory, and molecular orbital theor... |
Molecular orbital theory & predicting the stability of a molecule? |
$NaOH \rightarrow Na^+ + OH^- \ \ \ \ \Delta H ^o = -44.51 \ kJ/mol$
The dissolution of sodium hydroxide in water is an exothermic process, and so, according to Le Chatelier's principle, cooling the container should shift the reaction to the right. Shouldn't this mean that cooling the container will increase the so... |
What would happen if air heated to 1200 degree's Fahrenheit in a sealed environment was injected with colder air?
No specific pressure defined yet just a general idea of potential interaction between the two. |
First off, I know SiO2 is a network solid. I am looking at its intramolecular forces between the Si and the O molecule. On the one hand, it seems to me that this should be a polar covalent bond, but on the other, both electrons are given to the O by Si which makes it coordinate covalent.
So, fellow chemistry lovers,... |
Does SiO2 have polar covalent bonds or coordinate covalent bonds? |
What would happen if air heated to 1200 degree's Fahrenheit in a sealed environment was injected with colder air?
No specific pressure defined yet just a general idea of potential interaction between the two.
***-Edit-***
My apologies, I meant within a sealed environment like an engine cylinder. I know that the ho... |
We can predict whether a reaction can occur spontaneously by calculating the change in Gibbs' free energy.
I was just wondering whether there is any general measure of the thermodynamic stability of any substance?
Can I look at a random substance and using a table of thermodynamic values predict whether this sub... |
First off, I know $\ce{ SiO2 }$ is a network solid. I am looking at its intramolecular forces between the $\ce{ Si }$ and the $\ce O $ molecule. On the one hand, it seems to me that this should be a polar covalent bond, but on the other, both electrons are given to the $\ce O $ by $\ce{ Si }$ which makes it coordinate ... |
I am an engineer and I understand the difference between baking power and baking soda as baking powder *is* baking soda (alkali) with tartaric acid (acidic) and an inert starch (why? Is this a catalyst in the presence of humidity and temperature).
So why use [baking soda to deodorize a carpet](http://en.wikipedia.or... |
Is there any kind of program that is able to calculate the end result of a specific chemical reaction? Say I wanted to know what happens when you mix $HClO$ + $NaOH$, is there anything that could give me the answer to any question like this? Wolfram alpha works pretty good, but it doesn't give me an answer if it isn't ... |
Short answer? Possibly, but these ones aren't.
So, the other thing mentioned in the video is that the specific material he's using has a molecular weight of approximately four million. If we assume it's ordinary poly-ethylene oxide, we can get the rough number of $\ce{(CH2)2O}$ subunits by just dividing by the molec... |
1 mol of F2 is turned into 2F (atoms).
Is this the specific enthalpy of atomization, or two times that? |
What defines the specific enthalpy of atomization? |
Is there a combination of an acid and a base that when mixed results in a solution that is more basic or more acidic than the initial base or acid, respectively?
If so, do such combinations have a name? |
I am looking for hydrophilic polymers which are solid at room temperature and that don't dissolve in water. I need these for an experiment in which I condense droplets on a plate made out of/or coating with the polymer.
Just thinking `chemically' I imagine that any polymer with a lot of hydroxyl groups will be hydro... |
It's $$6e^-+ClO_{3}^- +6H^+ \rightarrow Cl^- + 3 H_2O$$
Now, with the gft of foresight, why was the equation for its oxidation not instead $$2e^-+ClO_{3}^- +2H^+ \rightarrow Cl^- + O_2+ H_2O$$
? Obviously it balances and charge is conserved. However, the latter equation would seem more likely: less charges have to ... |
In an acid, what does $ClO_3^-$ oxidise into? |
...but, most importantly, why? It's $$6e^-+ClO_{3}^- +6H^+ \rightarrow Cl^- + 3 H_2O$$
Now, with the gft of foresight, why was the equation for its oxidation not instead $$2e^-+ClO_{3}^- +2H^+ \rightarrow Cl^- + O_2+ H_2O$$
? Obviously it balances and charge is conserved. However, the latter equation would seem mor... |
In an acid, what does $ClO_3^-$ reduce into? |
It's given that the density of a gas(X) is 10 times that of hydrogen. In that case, what is the molecular weight of gas X?
Well what I've done up to now is this:
molecular mass of hydrogen=2
density of hydrogen= 0.089 kg/m3
Assuming that equal volumes(v) of both gases are taken,
mass of hydro... |
How to find the molecular weight of a given gas? |
I am looking for hydrophilic transparant materials which are solid at room temperature and that don't dissolve in water. I need these for an experiment in which I condense droplets on a plate made out of/or coated with the material
Just thinking `chemically' I imagine that any polymer with a lot of hydroxyl groups w... |
How does Sodium Bicarbonate act as a Deodorizing agent? |
Given a sample that is probably modafinil plus common fillers, but could be fake, what reagent tests would best determine whether it contains modafinil? Assume a known-good sample for comparison.
([Modafinil](http://en.wikipedia.org/wiki/Modafinil) is a sulfur-containing atypical stimulant which has become common in... |
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