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Recently I tried to hydrolyze some cellulose:
I added some acid to it ($\ce{H2SO4}$) then noticed nothing. Even after a few days there was no visible change and after doing some tests for glucose, those were negative too.
So at the end - expecting nothing would happen - I added some sodium hydroxide ($\ce{NaOH}... |
Carvone, $\ce{C_10H_14_O}$: <I>R</I>-(–)-Carvone is spearmint, <I>S</I>-(+)-carvone is caraway. Are the stereoisomers' graphs different? Quantitative indices generate a paradox that well-managed research fairs poorly in basic discovery (absent insubordination).
In counterbalance, a single failed reaction is a set... |
I held gallium under a heat lamp. I didn't melt. I didn't even find a thin film of liquid gallium. Can anyone explain why? Does gallium rust? |
Are some alkali metals better conductors than others? |
A Covalent bond involves overlapping of orbitals while an Ionic bond involves charge separation. Why is overlapping of orbitals less stronger than charge separation,i.e.,Why is an an Ionic bond is stronger than a Covalent bond? |
A Covalent bond involves overlapping of orbitals while an Ionic bond involves charge separation. Why is overlapping of orbitals less stronger than charge separation,i.e., why is an Ionic bond stronger than a Covalent bond? |
Essentiality of cooling/refrigeration for maintenance of taste and shelf life of food products including carbonated soft drinks? any technical guidance needed |
The position of equilibrium, I read, is dependent only on the relative Gibbs energies of the products and the reactants. Why is this so? Surely one must take into account the entropy of mixing, which wouldn't be dependent on the Gibbs energies, to work out the lowest point (energy wise) and find the position of equilib... |
Why does the position of equilibrium depend only on the relative Gibbs energies of the products and the reactants? |
The position of equilibrium, I read, is dependent only on the relative Gibbs energies of the products and the reactants. Why is this so? Surely one must take into account the entropy of mixing of the products and the reactants, which wouldn't be dependent on the Gibbs energies, to work out the lowest point (energy wise... |
How does cooling/refrigeration help in maintaining the taste and shelf life of food products, especially CSD (Carbonated Soft Drinks)? For example, chilled drinks have a nicer taste than a normal drink and may have longer shelf life. Why is that? |
The metal carbonyls (and similar organometallic compounds) involve a combination of sigma bond, a pi bond and backbonding. The bond strengths under consideration are the metal-carbon bond and the carbon oxygen bond. Here is the original question:-
> Predict the order of $\ce{C-O}$ bond strength in the following:... |
I'm doing a study a study on voltaic cells.
I've been working with them for a while and one of the questions that I've had is how does the salt bridge affect the cell. I mean, I know it allows ions to move and that it'a a basic component of the pill. But, does its' concentration affect the voltage of the cell itself?
... |
Assume that somebody wants to measure the sugar content of a liqueur. It seems that there are two types of Brix meters for it, ones which use the solution density and ones which use refraction of light.
If we have a meter intended for measuring the content of a sugar-in-water solution, but are using it for measurin... |
Are refractive or density based Brix meters better for use with alcoholic drinks? |
Assume that somebody wants to measure the sugar content of a liqueur. It seems that there are two types of Brix meters for it, ones which use the solution density and ones which use refraction of light.
If we have a meter intended for measuring the content of a sugar-in-water solution (and assume that we are talkin... |
Once I got going, this turned out to be a lengthy answer. So here's the summary: the alcohol will introduce a significant error in both methods. The density measurement will probably be closer to the actual sugar content. Th density measurement will underestimate the sugar, and the refractive index will overestimate th... |
Is there any chemical whose solubility increases with decrease in temperature ? |
I understand that all of these are made up of Carbon but I don't understand what differentiates them, since it is Carbon they all must be covalent bonds right? |
Whats the difference between graphite,nanotubes,and buckeyballs? |
Series A and B below can be viewed as two different ways to annulate an ethano bridge onto four-, five-, and six-membered rings. Using the ∆Hf° values given (in kcal/mol), how can calculate the strain energy for each compound? Could you also explain whether the trend seen in each series is consistent with expectations ... |
Finely divided magnesium in water corrodes, liberating hydrogen. "magnesium oil?" That is magnesium chloride in water. It is New Age hype. |
Is there any chemical substance, whose solubility increases with decrease in temperature ? |
Series A and B below can be viewed in two different ways to annulate an ethano bridge onto four-, five-, and six-membered rings. Using the $\Delta H_f^\circ$ values given (in kcal/mol), how can one calculate the strain energy for each compound? Could you also explain whether the trend seen in each series is consistent ... |
Doesn't dissolve in water? Filter it. Celite is your friend.
|
Also, why can some elements such as Fe have different ionic forms such as Fe2+ and Fe3+? What determines each form? |
Why don't B, C, Si, have ionic forms? |
I'm an AP Chemistry student, and we're doing the Decomposition of H<sub>2</sub>O<sub>2</sub> lab, in which we decompose H<sub>2</sub>O<sub>2</sub> with KI as a catalyst. I've gotten this data so far:
+-------+-------------+----------------+-----------+--------------+-------------+--------------+-----------------... |
How do I calculate the order of a reaction given slope? |
I'm an AP Chemistry student, and we're doing the Decomposition of H<sub>2</sub>O<sub>2</sub> lab, in which we decompose H<sub>2</sub>O<sub>2</sub> with KI as a catalyst. I've gotten this data so far:
+-------+-------------+----------------+-----------+--------------+-------------+--------------+-----------------... |
I'm just wondering, if one were to run a 11B NMR on a boron containing sample in a borosilicate tube, how could we separate the spectra of the tube and the sample? Apart from using a different tube - Perhaps through a pulse sequence like BIRD for 1H/13C? Or decoupling - which I've only just started to learn about and d... |
As mentioned, you don't want a direct answer so I am just going to ask you some question to think about, that hopefully help in getting you to the answer. Please reply in the comments whenever something is unclear to you!
You're expecting first order in both reactants, so if you would write down the reaction rate eq... |
I'm just wondering, if one were to run a $\ce{^{11}B}$ NMR on a boron containing sample in a borosilicate tube, how could we separate the spectra of the tube and the sample?
Apart from using a different tube - Perhaps through a pulse sequence like BIRD for $\ce{^1H/^13C}$?
Or decoupling - which I've only just s... |
Today I was making a pastille of Niobium Pentafluoride powder. The procedure includes a 6 ton squeezer, [precision wipes][1], silica gel, filter papers and acetone.
The first suspicious part was that on product details, $NbF_5$ was suppossed to be $5\mu m$ powder. Instead it looked like having hair(forgive my bad te... |
You can't simply filter it and take the feed because all the vegetables fiber remain in the filter with your starch. If you want to make a good starch you should start directly with the potatoes: grating the potatoes, putting them in hot water (preferably salted: this make more effective the separation from proteins) f... |
Like Fe, it can be Fe2+ or Fe 3+, same with Ni and Co, what determines whether the ionic compound will be Fe2+ or Fe3+? |
Why can some ions have different valence? |
You can't simply filter it and take the feed because all the vegetables fiber remain in the filter with your starch. If you want to make a starch with a decent level of purity you should start directly with the potatoes: grating the potatoes, putting them in hot water (preferably salted: this make more effective the se... |
1) In text books, the absorption event is usually described by a figure shown below<sup>1</sup>: light excites electrons to higher states in atom or molecule. The difference between the ground state and the excited one matches the energy of the absorbed light. But electron states in atoms and molecules should be quanti... |
Why is absorbance spectrum continuous and not quantized? |
![enter image description here][1]
So I have this homework question which I'm fairly sure I'm correct with, but apparently there are 4 choices. I think the bond wants to be most substituted so it moves around so would the correct choices be: A, E, F & G?
[1]: https://i.stack.imgur.com/m1N3m.png |
Am I on the right track? (NBS Question) |
The atomic radii are estimated using a variety of methods: most of these involve dividing their bond length by 2. But that is a very crude way of measuring atomic radii. I mean, atoms overlap each other when bonded, surely the actual atomic radius is much more than the one obtained by this method.
Why don't they sim... |
Why aren't atomic radii calculated using Schrodinger's equation? |
Your comment shows that you are on the right track.
You have chosen **A** and **C** because they are formed when the initial allylic radical **instantaneously** reacts with $\ce{Br2}$ in the propagation step of the reaction, isn't it? (*Hint: Just say YES!*)
Now give the **allylic radicals** corresponding to **A*... |
Erwin with his psi can do
Calculations quite a few.
But one thing has not been seen:
Just what does psi really mean?
(*Ernst Hückel*, english translation by *Felix Bloch*) |
No nodes should be introduced in the rotational interconversion between s-trans and s-cis of 1,3-butadiene. What is the explanation for that, if the one of the pi-systems should rotate 180 degrees? Two positive and negative lobs apparently turn upside down. |
Erwin with his psi can do
Calculations quite a few.
But one thing has not been seen:
Just what does psi really mean?
(*Ernst Hückel*, english translation by *Felix Bloch*)
Probably I oversee something and it is very easy. The Hamilton operator $\hat{H}$ for a multi-body problem of $K$ cores and $... |
Why aren't atomic radii calculated using Schrödinger's equation? |
Erwin with his psi can do
Calculations quite a few.
But one thing has not been seen:
Just what does psi really mean?
(*Ernst Hückel*, english translation by *Felix Bloch*)
Probably I oversee something and it is very easy. The Hamilton operator $\hat{H}$ for a multi-body problem of $K$ cores and $... |
Erwin with his psi can do
Calculations quite a few.
But one thing has not been seen:
Just what does psi really mean?
(*Ernst Hückel*, english translation by *Felix Bloch*)
It is not easy to perform the calculation that you called *simple*. The Hamilton operator $\hat{H}$ for a multi-body problem ... |
Erwin with his psi can do
Calculations quite a few.
But one thing has not been seen:
Just what does psi really mean?
(*Ernst Hückel*, english translation by *Felix Bloch*)
It is not easy to perform the calculation that you called *simple*. The Hamilton operator $\hat{H}$ for a multi-body problem ... |
I held gallium under a heat lamp. It didn't melt. I didn't even find a thin film of liquid gallium. Can anyone explain why? Does gallium rust? |
Erwin with his psi can do
Calculations quite a few.
But one thing has not been seen:
Just what does psi really mean?
([Erich Hückel][1], english translation by [Felix Bloch][2])
It is not easy to perform the calculation that you called *simple*. The Hamilton operator $\hat{H}$ for a multi-body pr... |
There is a reaction:
$\ce {ClF3 <=> ClF + F2} $
Then the equilibrium constant is: $\ce {Kc = 2,48 x 10^{-3}}$
At first, I have $\ce {[ClF3] = 0,25 M} $, $\ce {[ClF] = 0,031 M} $, and $\ce {[F2] = 0,02 M} $. Then I add some $\ce {F2} $ until the concentration of $\ce {F2} $ is $\ce {0,1 M} $.
The question is... |
I wondered if it was possible to predict the product(s) of a reaction (or even the equilibrium) based on the reactants and the temperature/pressure.
I found an answer to a similar question [here][1]:
> No, there is no such thing as chemical reaction are not that easily
> predictable. You can get result right in so... |
The equation $2.48\times 10^{-3} = \frac{(0.1-x)(0.031-x)}{0.25+x}$ is correct, but it simplifies to a second degree polynomial, so it has two solutions, not one. You just picked the incorrect root (negative concentrations have no physical meaning). Can you find the right answer now? |
Why can a solvent dissolve only a particular amount of solute?
If we add more solute to the solution, the number of solute particles in contact with water increases. So rate of dissolution should increase, and subsequently, the solubility product should also increase. But why do we have a constant value of solubility... |
Why do solutions become saturated? |
Why can a solvent dissolve only a particular amount of solute?
If we add more solute to the solution, the number of solute particles in contact with water increases. So rate of dissolution should increase, and subsequently, the solubility product should also increase. But why do we have a constant value of solubility... |
The electron configuration of calcium is 2, 8, 8, 2, where up to that point each shell, asides from the first shell counts up to 8 - why then does scandium have an electron configuration of 2, 8, 9, 2?
What causes the 3rd shell to start filling up, rather than the fourth? |
Why does the 3rd electron shell start filling up with scandium? |
Enantiomer of a Diels-Alder reaction? |
![enter image description here][1]
I don't know how to draw it, I really thought what I initially had was correct, should I make a trans reactant or is there something else missing?
[1]: https://i.stack.imgur.com/vSzCD.png |
Mono-addition of HCl to unsymmetrical dienes? 3/4th of the answer completed |
I am dealing with the dissociation of water into its components hydrogen and oxygen and I am trying to determine the standard gibbs free energies of each component. My professor said if the substance is an ideal gas in the standard state then
$$g_{i}^{0}=g_{i}^{pure IG}(T, P_{ref})$$
Now this means I can determin... |
Determining standard Gibbs free energy for water? |
Transition metals can form stable ions with different oxidation states. But I am confused why doesn't only the most stable state exist... let me clarify my question more:
$$Ti^{2+} ---> Ti^{3+} + e^- $$
The $E$ value= +0.5V
This just shows that $Ti^{3+}$ is more stable. So my question is that why doesn't $Ti^{3+... |
In most high school chemistry books, it is said that the delocalised electrons in benzene makes it particularly stable. However, how does it contribute to stability? Is there any simple way of understanding this? |
Do we agree that the first step ist the addition of a proton to the diene? This is bit different from the addition of HCl to an alkene, where you would rely on the **Markovnikov** rule.
Here, stabilization of the cation through resonance comes into play.
> I don't know how to draw it [...]
Draw stepwise!
!... |
I wondered if it was possible to predict the product(s) of a reaction (or even the equilibrium) based on the reactants and the temperature/pressure.
I found an answer to a similar question [here][1]:
> No, there is no such thing as chemical reaction are not that easily
> predictable. You can get result right in so... |
When a pass a construction site where someone is welding two pieces of metal together there is a very distinct smell that I associate with 'burning' metal, although I am not quite sure it is burning in the traditional sense. Also, when someone ignites a [sparkler][1] this same (or at least similar) smell emerges.
I ... |
What is the smell of 'burning' metal? |
My textbook says that $[\rm{CrF_6}]^{3-}$ is an example of $sp^3d^2$ hybridization. But I don't really see how. Chromium has an electronic configuration of:
$$3d: \boxed{\uparrow}\boxed{\uparrow}\boxed{\uparrow}\boxed{\uparrow}\boxed{\uparrow} \ 4s: \boxed{\uparrow}$$
Give three more electrons and it might look s... |
How does $[\rm{CrF_6}]^{3-}$ hybridize? |
Summary
------
Okay, so after doing some serious number crunching and searching for literature values all over the web, I've come to the following conclusion: **Yes, it is possible to survive in these conditions!**
Plausibility of Environment
--------
First, let us examine the plausibility of the environment... |
I have a solution containing glucose and some sulfuric acid. I want to distill out the sulfuric acid to then reuse it for other purposes. But there is glucose present in the solution - I'm afraid that, when increasing the temperature, the sulfuric acid will dehydrate glucose to carbon and other compounds - something th... |
The question goes:-
> p-cresol (*4-methylphenol*), on reacting with chloroform
> ($\ce{CHCl3}$) in alkaline medium, gives [Riemer-Tiemann reaction][1].
> Which of the following is correct regarding the products and their
> abundance, i.e. mention the major and the minor product.
>A. 2-hydroxy-5-methyl ... |
Transition metals can form stable ions with different oxidation states. But I am confused why doesn't only the most stable state exist. Let me clarify my question more:
$$\ce{Ti^{2+} -> Ti^{3+} + e^-} $$
With $E^0 = +0.5~\mathrm{V}$.
This just shows that $\ce{Ti^{3+}}$ is more stable. So my question is that why ... |
Why are lithium salts heavily hydrated? I am not able to understand this because I feel salts of larger cations like Caesium should be more hydrated because of the larger size, they can able to hold more water molecules.
What is the flaw in my reasoning? Pls help
|
Why are lithium salts heavily hydrated? I am not able to understand this because I feel salts of larger cations like Caesium should be more hydrated because of the larger size, they can able to hold more water molecules.
What is the flaw in my reasoning?
|
We know that
$c^2=\frac{\partial p}{\partial ρ}$
The adiabatic compressibility is defined as: $\beta_S=-\frac{1}{V}\frac{\partial V}{\partial p}$ such that the subscript "S" stands for "adiabatic"
How can I show that $c^2=\frac{1}{\rho \beta_S}$ ?
I tried replacing $V$ by $\frac{m}{\rho}$ but I get for $\beta... |
Why are superoxide ions stable only in presence of large cations suc as K, Rb and Cs? |
My mom while making Potato chips put some Baking Soda in Oil with it. Just curious to know, it was first time Baking Soda in Oil at that high temperature. Is it safe to eat?
Answer ASAP before my chips get cold. |
If 125 Calories of heat is applied to 60.0-g piece of copper at 21.0 degree C, what will the final temperature be? The specific head of copper is 0.0920 cal/gC.
|
The flavor of fine fried potatoes is from browning, the Maillard reaction. Carbonyls (sugars) condense with amino groups (alanine residees in protein) to Schiff bases, then the fun starts. The optimum pH for condensation is bicarbonate buffer, slightly basic. One might then do the experiment of soaking fries in dilu... |
If 125 Calories of heat is applied to 60.0-g piece of copper at 21.0 degree C, what will the final temperature be? The specific head of copper is 0.0920 cal/gC.
All I have to answer this question is a formula:
SH = heat/(mass x delta T)
|
In terms of inexpensive, safe, and a little polar to move oxidation products, I'd try soaking in and flushing with hot soybean oil (replace elastomer hoses and seals). Then flush with kerosene (odorless white spirits, hardware store paint section), then blow out with compressed air.
Carburetor cleaner was mixed cr... |
The definition of voltage I'm familiar with is the amount of electric potential energy per unit charge at a location. My prof defined the voltage of a battery to be the amount of potential energy difference an unit charge would have at the positive terminal vs. the negative terminal.
But from what I remember from h... |
What's the voltage of a battery? |
Why does anything dissolve at all? The binding energy (lattice energy) of the solid must be compensated by solvation and entropy of the solution. Like dissolves like (then cheats, like clathrates and micelles). As the solution concentrates, incremental driving energies diminish.
Don't think about adding water to ... |
When choosing a cup of tea, I can choose a big cup or a small cup. I'm wondering if I get more caffeine with the bigger cup or the same amount of caffeine. (in moles)
My question is: **For a given teabag and dunking duration - will I get more caffeine in a bigger cup or the same amount?**
|
For a given teabag and dunking duration - will I get more caffeine in a bigger cup or the same amount? |
I am curious why **ester** is used often as a solvent in organic chemistry? How is it different that just using water, which is also polar? I'm am sorry if this is an basic question, I'm just a student. |
Homework help? Calculating enthalpy changes? |
How do you prepare you your cup of tea?
Dunking the leaves of tea (solid phase) exposes them the liquid phase (water). The concentration in the liquid phase of caffeine (and other chemicals/ingredients carried by your leaves of tea) will increase. Because hot water is more efficient than cold one for this extractio... |
When choosing a cup of tea, I can choose a big cup or a small cup. I'm wondering if I get more caffeine with the bigger cup or the same amount of caffeine. (in moles)
My question is: **For a given teabag and dunking duration - will I get more caffeine in a bigger cup or the same amount?**
**Assumptions**
* Tea... |
*Can anyone please help me with this homework? Please give as much details as possible.*
The SN1 solvolysis of one of the following alkenyl bromides is in MeOH approximately 100000
times faster than the other one. Which is the more reactive one? Draw the mechanism including the transition state, determine the rate... |
How do I calculate the enthalpy change when a gas is being used to heat water? |
Which of the these SN1 solvolysis of two alkenyl bromides reactions is faster? |
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