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Which synthetic resins are suitable for fabrication of plumbing components e.g pipe sections?<br>
I'm trying to find an easy way to mold/house/en-case a custom designed data logger.
Water Temps range between 10 to 50 deg C.
|
Which synthetic resins are suitable for fabrication of plumbing components e.g pipe sections?
I'm trying to find an easy way to mold/house/encase a custom designed data logger.
The water temperature ranges between 10 to 50 degrees C.
|
I'm working on a lab report that has some specific questions that need to be included. The lab work itself dealt with GC-MS.
What is the effect of the temperature selected during Cryofocusing/Cryotrapping? What is the effect of making this temperature warmer or colder?
My understanding was that the gas based samp... |
What is the effect of temperature during Cryotrapping? |
Is $\ce{Mn(C2H3O2)2}$ soluble in water? |
It is well known that when you add salt to ice, the ice not only melts but will actually get colder. From chemistry books I know that salt will lower the freezing point of water. But I'm a little confused as to why it results in a drop in temperature instead of just ending up with water at 0C.
What is occurring when... |
Why does ice water get colder when salt is added? |
How is HSO4- formed? If Hydrogen is 1+ and S04 has 2- charge? I don't understand this. Could someone please clarify? |
How is the acid HS04- formed? |
Here's is what I understand so far and the following is referenced directly from UNSW CHEM1061 lecture notes by Professor Pall Thordarson:
- order of the reaction SHOULD be equal to the number of molecules of that reactant involved in each collision ( however this is not always the case)
- it is only possible to ... |
What is the reaction order of a reaction? |
How is $\ce{HSO4-} formed? If Hydrogen is 1+ and $\ce{S04} has 2- charge? I don't understand this. Could someone please clarify? |
How is the acid $\ce{HS04-}$ formed? |
How is $\ce{HSO4-}$ formed? If Hydrogen is 1+ and $\ce{SO4}$ has 2- charge? I don't understand this. Could someone please clarify? |
How is the acid $\ce{HSO4-}$ formed? |
Which synthetic resins are suitable for fabrication of plumbing components e.g pipe sections?
I'm trying to find an easy way to mold/house/encase a custom designed data logger.
The water temperature ranges between 10 to 50 degrees C.
EDIT: I'm planning this for both indoor & out door use. Under direct sunlight... |
Why meth oxide anion is negatively charged?
It has 13 valence electrons and having 13 free electrons in spite of that meth-oxide anion is
negatively charged.
please help.
Debittree
|
Why meth oxide anion is negatively charged?
It has 13 valence electrons and having 13 free electrons in spite of that meth-oxide anion is
negatively charged.
please help.
|
Why meth oxide anion is negatively charged?
It has 13 valence electrons and having 13 free electrons in spite of that meth-oxide anion is
negatively charged.
|
If I have a system in which I introduce 100e.u.F (energy units) derived from chemical energy (i.e. fuel) and generate thermal energy to heat water what are e.u. absorbed by water? I.e. the efficiency of the transformation?
Basically I would like to know the "average/general" efficiency of energy transformation f... |
Unfortunately not, I'm afraid.
I think you might have gotten cause and effect mixed up here. Blue flames are hotter than yellow flames not because of their color, but because *hotter flames generate blue light and cooler ones generate yellow/red light*.
To take an example of this kind of problem, I know that very... |
I am trying to learn simulation myself and i have installed matlab in my machine for that purpose. In web i have gone through some of the basics of [montecarlo simulation][1] but i am unable to find a simple montecarlo simulation expereiment for chemistry. I am trying to simulate growth of a nanoparticle during a wet s... |
Why is the methoxide anion negatively charged?
It has 13 valence electrons and has 13 free electrons. In spite of that the methoxide anion is negatively charged.
|
For a research project, I'm looking into existing chemical molecules that have the following properties:
* It is mostly chemically inert, safe for animals and children
* It exhibits piezoelectricity - production of high electric oscillating potentials under pressure
* paramagnetic moment a plus, but not required... |
Here's is what I understand so far and the following is referenced directly from UNSW CHEM1061 lecture notes by Professor Pall Thordarson:
- order of the reaction SHOULD be equal to the number of molecules of that reactant involved in each collision ( however this is not always the case)
- it is only possible to ... |
I have seen vacuum take-off adapters that are essentially plugs, which could be placed at the top of a three-way above the fractionating column, and also straight and bent vacuum take-offs with an inner stem that seem meant to be placed right before the collection vessel.
Would there be any difference in which plac... |
A battery, at its heart, is what we call a redox cell: some compounds are stripped of their electrons, and others gain those electrons. The movement of electrons between these two compounds can be harnessed to provide electricity, but that's taking us a step too far. What we want to understand here is why the electrons... |
In many cultures, human dead bodies are burnt to ashes, which is then thrown in rivers and some time buried in earth.
Are human ashes after burning dead bodies biodegradable?
Note: Earlier I posted this question [here][1]
But I was suggested to post it here.
[1]: http://discuss.area51.stackexchange.com/ques... |
Dead-body Ashes: biodegradable or not? |
As the electrons fall from higher levels to lower levels, they release photons. Different "falls" create different colors of light. A larger transition releases higher energy (short wavelength) light, while smaller transitions release lower energies (longer wavelength).
The visible wavelengths are caused a by sing... |
According to [one source][1], the major elemental constituents of cremation remains are calcium and phosphorus, presumably from the hydroxylapatite in bone (which consists primarily of calcium phosphate). The rest is mainly assorted trace metals, which exist in relatively minute concentrations in the human body and don... |
- In a Pourbaix diagram (E-ph diagram) where the regions are given , but the assignment of these to the elements we have is not done yet , how can the oxidation numbers helps me out assigning each element in its appropriate region ? |
Why is the methoxide ($CH_{3}O^{-}$) anion negatively charged?
It has 13 valence electrons and has 13 free electrons. In spite of that the methoxide anion is negatively charged. |
I've always heard that different isotopes of the same element have exactly the same chemical properties. But for example, I've read that some compounds which have hydrogen atoms interchanged by deuterium become odorless (this is one of the arguments for the [vibrational theory of olfaction][1]).
So, are situations ... |
I've done a little simulation as a senior year elective, though not in Matlab. Can you be a little more specific about how/what you're trying to model with nanoparticle growth? Perhaps direct us to an abstract or two.
The first Monte Carlo simulation you should attempt is the drunken sailor problem. The basic idea i... |
The major issue with the blood-brain barrier is that aside from small hydrophobic/lipophilic compounds (including $O_{2}$ and $CO_{2}$), almost everything else is prevented from passing due to cellular tight junctions and will only (potentially) pass through via active transport.
However, for small lipophilic molecu... |
We know that the molecule of $H_2O$ is V-shaped. This is what makes it a dipole.
![enter image description here][1]
[1]: https://i.stack.imgur.com/vdU57.png
But why is that? I mean, if the hydrogens have a partial positive charge, then they should try to get away from each other, until they are diametrica... |
Why is $H_2O$ V shaped? |
I am running experiments using reagents preserved with 0.1% sodium azide, which are applied to a gold film. Unfortunately, there are very few options for using reagents without sodium azide.
I understand that sodium azide reacts with gold to form heavy metal azides, which are explosive.
I would like to know:
... |
From what you have given, this question can not be answered in terms of electrons.
It is meaningless to do any electron calculation, because you have to know it has one negative charge before you can do the electron counting. How can you get a correct Lewis structure without knowing that it has one extra electron? T... |
Why is carbon dioxide that comes from dry ice opaque and smoky while the carbon dioxide that we exhale transparent? |
Why is the carbon dioxide we exhale transparent? |
I have read that in VSEPR theory, multiple bonds are considered or treated as single bonds when predicting the geometry of a molecule? I've read in yahoo answers that it is because only sigma bonds are used in determining their shape. What's the reasoning behind this? Please help. |
Why are sigma bonds the only ones used in determining the geometry and bond angle in VSEPR theory? Why aren't Pi bonds used? |
In the titration of a solid acid, an endpoint is reached after 22.0mL of 0.120 M NaOH has been added. Assuming that each acid particle contains two acidic hydrogens and both are neutralized, what is the molar mass of the unknown acid?
I really don't know how to solve this. I've figured out how to calculate the moles... |
The following equation is standard in thermodynamics:
$$
\Delta G^\circ=-RT\log(K)
$$
where $K$ is the equilibrium constant. In dimensional analysis, Bridgman's theorem tells us that the argument of a transcendental function (like $\log$) must always be dimensionless. But $K$ may have dimensions (depending o... |
Dimensional analysis of the reaction isotherm equation: contradiction of Bridgman's theorem? |
I am not from chemistry background. Could you tell me in simple words what is activity of hydrogen ? ( -log of activity of hydrogen gives pH ) |
This link contains information on the general toxicity of non-ionic surfactants such as Triton X-100: http://ec.europa.eu/health/opinions/products-resembling-food/en/l-3/4-products-dangerous-swallow.htm#2p3
In summary:
- They cause mild irritation to mucous membranes
- This is primarily due to foaming
- Foaming... |
Regarding caustic injury to gastric, oesophageal or small bowel, Triton X-100 has a pH of 9.7 at 100% concentration (according to Wikipedia) which can cause alkaline caustic injury, however it is less likely to cause severe full thickness injury, as those injuries tend to happen with ingested products of pH <2 or >12.5... |
## Caustic Ingestion Injury ##
Triton X-100 has a pH of 9.7 at 100% concentration (according to Wikipedia) which can cause alkaline caustic injury, however it is less likely to cause severe full thickness injury, as those injuries tend to happen with ingested products of pH <2 or >12.5 or with other corrosive proper... |
As @udiboy said, this question belongs on Chemistry.SE.
The number of valence electrons in an atom is the *number of electrons present in the outermost orbit of the atom*, NOT adding up the electrons of the last 2 shells. Each orbit can have only a certain number of electrons. That number is equal to $2n^2$, where ... |
I need to understand the following:
Considering an element Sulfur - S which has 16 electrons.
How do we calculate the valence electron of S?
Please correct me if I am wrong:2+2+6+2+4=16. So, the valence electron = 4+2=6
Is it that always valence electron is the addition of the last two shells? In that case ... |
How to find the number of valence electrons? |
I need to understand the following:
Considering an element Sulfur - S which has 16 electrons.
How do we calculate the number of valence electrons of S?
Please correct me if I am wrong:2+2+6+2+4=16. So, the valence electron = 4+2=6
Is it that always valence electron is the addition of the last two shells? In... |
I am not from chemistry background. Could you tell me in simple words what the activity of hydrogen $a_{\ce{H+}}$ is? It arises in the context that the negative logarithm of the activity of hydrogen gives the pH: $\text{pH} = -\log_{10} a_{\ce{H+}}$. |
> "In the titration of a solid acid, an endpoint is reached after 22.0mL
> of 0.120 M NaOH has been added. Assuming that each acid particle
> contains two acidic hydrogens and both are neutralized, what is the
> molar mass of the unknown acid?"
I really don't know how to solve this. I've figured out how to calcul... |
(this is a comment to Phillip answer; upon editing it failed to get saved on due time)
Basically $K_c$ is valid as long as the solutions show colligative properties. These "concentration" constants can (should?) be defined dimensionless, and can use different units for the concentration, like $[c]/c^\circ$ where $[c... |
(this is a comment to Phillip answer; upon editing it failed to get saved on due time)
Basically $K_c$ is valid as long as the solutions show colligative properties. These "concentration" constants can (should?) be defined dimensionless, and can use different units for the concentration, like $[c]/c^\ominus$ where $... |
(this is a comment to Phillip answer; upon editing it failed to get saved on due time)
Basically $K_c$ is valid as long as the solutions show colligative properties. These "concentration" constants can (should?) be defined dimensionless, as they properly emerge as a limit for the dimensionless activity in "ideal" sy... |
The oncotic pressure or colloidal osmotic pressure is the osmotic pressure developed due to the presence of colloids in a solution. But since the colloids are not true solution, why should the colloids be termed as solutes soluble in the solvent and consequently capable of producing any osmotic pressure? Should not the... |
colloidal osmotic pressure? |
I've recently had several jerry-cans of oil (awaiting disposal) topple over in the attached garage, and several rooms following influx of water following heavy rain. After the water level receded the floor is left with a thin layer of burnt oil.
Various sites on the net recommend using sawdust, baking soda etc. I'm ... |
A stoichiometric fuel-air mixture flowing in a Bunsen burner forms a well-defined conical flame. The mixture is then made leaner. For the same flow velocity in the tube, how does the cone angle change?
Thanks. |
I was reading up on a wonderful little chemical compound known as chlorine trifluoride ($\ce{ClF3}$). For a primer, check out Dr. Derek Lowe's blog post here: [Sand Won't Save You This Time][1]. The title of the post is quite telling; this compound is so reactive with other compounds - any other compound, really - that... |
How can silver work as a disinfectant in a bathtub if precipitates in the presence of chloride? |
A stoichiometric fuel-air mixture flowing in a Bunsen burner forms a well-defined conical flame. The mixture is then made leaner. For the same flow velocity in the tube, how does the cone angle change?
|
Do ions also form special electron configurations? (just as Copper and Chromium do)
I know that because copper has 1 electron in its s-orbital (highest) because it wants to have a full d-orbital (d^10)
But do ions also act this way? |
Do ions also form special electron configurations? (just as Copper and Chromium do) |
I am really confused about what the size of particles of dispersed phase in a colloid is: one of my textbook says its between $1 - 100nm$, another says its between $1-1000nm$, and Wikipedia says its between $2-500nm$. Is there any reliable source giving the exact information? |
Size of dispersed phase particles in colloid? |
I have written some molecular dynamics code that I want to use to model known chemical reactions.
By known I mean that it has been observed in a lab that A+B->C.
I am not interested in finding out if it is feasible that two things react (i.e. is there a favorable energy configuration?), rather I am interested i... |
How should I modify my molecular dynamics simulation so that known chemical reactions can be modelled? |
One reaction used to form sodium hypochlorite (A type of bleach) is as follows:
2NaOH(aq)+Cl2(g)-->NaOCl(aq) + NaCl(aq) + H2O(l)
Provided the sodium hydroxide is dissolved in some substance.
I know that the sodium hydroxide dissociates to form the Na+ and OH- ions, but I do not know why the Cl2 breaks down... |
One reaction used to form sodium hypochlorite (A type of bleach) is as follows:
$\ce{2NaOH(aq)+Cl2(g)-->NaOCl(aq) + NaCl(aq) + H2O(l)}$
Provided the sodium hydroxide is dissolved in some substance.
I know that the sodium hydroxide dissociates to form the Na+ and OH- ions, but I do not know why the Cl2 breaks d... |
One reaction used to form sodium hypochlorite (A type of bleach) is as follows:
$\ce{2NaOH(aq) +Cl2(g)-->NaOCl(aq) + NaCl(aq) + H2O(l)}$
Provided the sodium hydroxide is dissolved in some substance.
I know that the sodium hydroxide dissociates to form the Na+ and OH- ions, but I do not know why the Cl2 breaks ... |
I have written some molecular dynamics code that I want to use to model known chemical reactions.
By known I mean that it has been observed in a lab that $\ce{A +B->C}$.
I am not interested in finding out if it is feasible that two things react (i.e. is there a favorable energy configuration?), rather I am inte... |
I think there might be a bit of a misunderstanding about what causes the osmotic pressure.
Therefore, I will give a short description of what osmotic pressure is:
Osmosis occurs when two solutions of different concentrations are separated by a membrane which will selectively allow some species, say the solvent, throu... |
One reaction used to form sodium hypochlorite (A type of bleach) is as follows:
$\ce{2NaOH(aq) +Cl2(g)->NaOCl(aq) + NaCl(aq) + H2O(l)}$
Provided the sodium hydroxide is dissolved in some substance.
I know that the sodium hydroxide dissociates to form the $\ce{Na+}$ and $\ce{OH-}$ ions, but I do not know why th... |
One reaction used to form sodium hypochlorite (A type of bleach) is as follows:
$\ce{2NaOH(aq) +Cl2(g)->NaOCl(aq) + NaCl(aq) + H2O(l)}$
Provided the sodium hydroxide is dissolved in some substance.
I know that the sodium hydroxide dissociates to form the $\ce{Na+}$ and $\ce{OH-}$ ions, but I do not know why th... |
In ionic compounds, where does the extra electron go? Or, in case of a cation, from which shell does it come?
Consider, for example, $OH^{-}$, where did this extra electron go in the electronic configuration? And, what about $OH^{+}$? There exists no such ion. Why?
|
Where does the extra electron go in ionic compounds? |
If you look at $\ce{Na}$, it has a very low ionization energy, but the question is, why does it have an ionization energy at all? If it can get to the electronic configuration of $\ce{Ne}$, by losing an electron, which is a very stable configuration, then it should release energy. Consider the analogy to gravitational ... |
Why does sodium require energy to ionize? |
I think, first I should clarify what causes the osmotic pressure:
Osmosis occurs when two solutions of different concentrations are separated by a membrane which will selectively allow some species, e.g. the solvent, through it but not others, e.g. the solute.
So, there is a concentration gradient between the two sol... |
If you look at $\ce{Na}$, it has a very low ionization energy, but the question is, why does it have an ionization energy at all? If it can get to the electronic configuration of $\ce{Ne}$, by losing an electron, which is a very stable configuration, then it should release energy. Consider the analogy to gravitational ... |
There are two very different questions here so let's break things down a bit
##Why does sodium have an ionization energy?##
Since electrons are negatively charged and nuclei (owing to the presence of protons) are positively charged, electrons will typically be drawn to the nucleus. The situation gets a bit more co... |
There are two very different questions here so let's break things down a bit
##Why does sodium have an ionization energy?##
Since electrons are negatively charged and nuclei (owing to the presence of protons) are positively charged, electrons will typically be drawn to the nucleus. The situation gets a bit more co... |
It seems that every website on sexual health advises against using oil-based lubricants with condoms. It is claimed that "oil breaks down latex". One source claimed that a latex condom completely breaks down in only 60 seconds. It made me curious, so I made an experiment.
I took a piece of rubber latex condom and so... |
Oil breaks down condoms? |
I wrote out an answer to this but realized I was wrong. But I've noticed a number of things:
First off, your form of the ideal gas law has the Molar Mass inverted. If you make the substitution that $n=m/M$, then the rearrangement reads $m = MVp/RT$, you have the $M$ on the bottom.
Secondly, You are selecting a Vo... |
How can I calculate the energy of a solution by knowing all of it's elements?
**For example:**
If I have 2 liters of salting water $NaCl_{(aq)}+H_2O_{(l)}$ contains 1.5 g of salt, how can I determine the energy stored in it? |
How can I calculate the energy of a solution by knowing all of it's elements? |
In his book on molecular orbital theory, *Molecular Orbitals and Organic Chemical Reactions*, Ian Fleming notes that Pauling formulated an early alternative model to Huckel theory for explaining the bonding of simple conjugated polyenes. Evidently, this came to be called $\tau$-bonding. Fleming describes it as a modifi... |
What utility does the Tau bond model of orbital overlap have? |
How will the transference number of H+ ion in a dilute solution vary as temperature increases? |
How do you calculate how much energy is needed to break a water molecule into its constituent atoms? |
How much energy is needed to break a water molecule? |
How can I calculate the energy of a solution by knowing all of it's elements?
**For example:**
If I have 2 liters of salting water $NaCl_{(aq)}+H_2O_{(l)}$ contains 1.5 g of salt, how can I determine the internal energy stored in it? |
How can I calculate the internal energy of a solution by knowing all of it's elements? |
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