# All Questions

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### Does secondary pentane exist? If so, how can it be determined?

I'm starting the very basics of hydrocarbons and I'm having a hard time at understanding when to use the common/trivial name prefixes (sec, iso, neo..etc) One particular problem is the difference ...
9 views

### Do chain shaped molecules have higher thermal velocity in gases?

As far as I understand the thermal velocity depends on the degrees of freedom of the actual molecule. Does this mean that for example the thermal velocity of butane is bigger than the thermal velocity ...
9 views

### When will heating aluminium cause oxide formation

I am trying to heat aluminium from the coca cola cans. As I fire it will a butane torch, seems to form the oxide of aluminium. My question is under what circumstances will the metal melt and under ...
14 views

### About the use of Pascal or atmosphere in chemistry

I was wondering if there are specific formulae in chemistry for which it is "compulsory" or convenient to use atmosphere (atm) rather than Pascal (or even mmHg) as a unit of measurement. Of course ...
8 views

### Can chloride concentration be measured as CaCO3 mg/l

I work in a chemical analysis lab. today I received a sample from a client who wants chloride concentration expressed as ppm of CaCO3. I suspect it's a mistake but I am not sure if there is any ...
13 views

### How dangerous is the Mercury-Thallium filled thermometer?

What's the amount of Mercury and Thallium in a typical low-temperature thermalmeter? How poisonous is Thallium when bounded with Mercury?
19 views

### Reason for the generation of London Dispersion Forces

While talking about gaseous state of matter we came to the topic of London Dispersion Forces while are caused by the generation of dipole in one atom which induces a dipole in another. While talking ...
29 views

### Finding the central atom of N2O

Why do all structures of $\ce N_2\ce O$ have Nitrogen as their central atom? Can we not draw a lewis structure with Oxygen as the central atom with 2 double bonds to the two nitrogens? This will still ...
10 views

### Chemical Equation for the reaction of Allura Red AC with NaClO

I am trying to figure out the chemical formula for the reaction between Allura Red AC and NaClO(bleach). I have never met such reactions before in my study and I was unable, or maybe looked in the ...
15 views

### method of separating product and conserving the catalyst

I'm looking for a way to separate reaction product of iodobenzene with ethyl 2-methyl-3-oxopentanoate in 1,4-dioxane (toluene is an alternative as a solvent). The catalyst being used is Pd2(dba)3 with ...
31 views

### why Ammonia is proton acceptor

I understand that this is an elementary question, but I tried to find answers which I could not get. I am trying to understand why Nitrogen in Ammonia is a proton acceptor. Now as I can see from the ...
11 views

### Question about calculating parts per million by mass

I'm having trouble understanding the concept and calculation of ppmm. The problem is calculating the abundance of molecule X in the atmosphere. Molecule X has a molar mass of 200 g/mol, the mass of ...
11 views

### Is fluorinated steel corrosion resistant from normal oxidation?

I've recently learned of a compound named Chlorine trifluoride a powerful fluorinating agent. The common way to store it seems to be in regular steel drums where it flash oxidizes the inside of the ...
8 views

### Question on comparing surface tensions of different molecules

I am comparing the surface tensions of three molecules: $$\ce{CCl4}$$ $$\ce{CH3CH2OCH2CH3}$$ $$\ce{CH3OH}$$ This table from Wikipedia lists the surface tension for each molecule. Based on those ...
16 views

### What is happening on a microscopic level in precipitation reactions?

This is my first-ever post on StackExchange, so please tell me if there are any problems to my post. Question: What is happening on a microscopic level when a precipitate forms? I understand ...
28 views

### What is the stability of the following cyclic compounds?

I came up with a few examples 1 What i do know is that sp2 hybridised carbon is -I effect showing group and sp3 hybridised carbon is +I effect showing group. But in the first compound there is ...
26 views

### Historic Importance of Tin(Sn)

How important is tin for a bronze age society when there's many copper alloys including arsenical bronze. If you're out of tin whats the next best copper alloy(s) for making shortswords and axe blades ...
25 views

### Eletrolytic rust removal

I've seen quite a few youtube videos about electrolysis for rust removal. The process seems to be effective. My question is: how does it work? I get that the water is ionised so we have O- and OH+ ...
38 views

### How would one determine an element simply by looking at its binding energy?

I am self studying MIT OCW chemistry 5.111 2014, one of the lecture questions states the following: Consider a neutral atom with 8 distinct electron binding energies: −14 eV, −28 eV, −94 eV, −218 ...
8 views

### What safe non-permanent adhesive is used to attach things like saxophone mouthpiece cushions so they are safe to go in a user's mouth? [on hold]

I'm developing a product that will be a musical instrument mouthpiece. I need to make available user-installable, user-removable "mini reeds" to be molded out of a food safe elastomer. I propose to ...
21 views

### Why palladium chloride not react with stannous chloride?

I want to make a Palladium Tin Colloidal Activator for plating a non-conductive surface using this tutorial Tutorial video. When I put the palladium chloride ...
25 views

### alpha-alkylation/arylation

I have a question about alpha arylation/alkylation. For example, the reaction of ethyl acetoacetate with iodopropane. I've seen some synthesis carried out using sodium ethoxide as a base. Assuming ...
20 views

### When dissolving an ampholyte- acid/base, is the solution acid or basic? [on hold]

Consider the weak acid HCN, when dissolved there are CN-ions and hydroxonium-ions. Since the acid constant is less than the basic constant, will the solution be basic? Or will there be barely any CN-...
12 views

### Interface level between 2 components in Liquid-Liquid Extraction, What does it mean?

In LLE physical processes, there is this level (interface) between the 2 components (for example) that is being separated as shown in the picture. I know that the height of this level from the ...
25 views

### How Pressure affects vapor pressure in a closed container

Let's say you had a container with a lid that had a certain vapor pressure at sea level. Let's say you walk up to Mount Everest. Up there, the pressure is significantly less than the Is the vapor ...
36 views

### What is the function of toluene in this reaction?

I'm trying to find the mechanism for this reaction: My (tentative) thought for a possible mechanism is: EDIT: New thought for mechanism: But this leaves some loose ends that I haven't been able to ...
21 views

I have a doubt regarding the formation of intermediates when an alkane and a vinyl molecule are present. I've attached the snap of the reaction. Please help me out whether/why the reaction proceeds ...
12 views

### Melting Temperature of PolyHEMA [on hold]

can anyone link me to any literature that specifies the melting point of polyhema? Thank you.
20 views

### Confusion in calculations of the First law of Thermodynamics regarding Internal energy and enthalpy [on hold]

Below calculations are based on assumption that the gas is ideal. / Under constant temperature, volume:- Change(E) = q(v) Now E is a state function. So change(E) should be the same irrespective of the ...
25 views

### Sand Dissolution in Water [on hold]

Are there any ambient conditions which would allow silica to dissolve in water? At RTP silicic acid has a maximum concentration of ~100ppm, but at what pressure and temperature ranges would this ...
27 views

### Can NaCN or HCN be used as sources of cyanide ion in substitutions? [duplicate]

When cyanide ions act as nucleophiles in substitution reactions, why is KCN the reagent of choice? Would some other source of cyanide such as NaCN or HCN work equally well in the reaction, since they ...
18 views

### identify the functional group [on hold]

find the functional group for the following compunds. Thank u so much
7 views

### Software platforms with integration of multi vendor mass spectrometer device data?

I know about ACD/Spectrus Processor which is a software platform to integrate analytical chemistry data from multiple mass spectrometer device vendors (e.g. Agilent Technologies, Bruker, Waters) to ...
19 views

### How to remove NaCl from Ca(OH)2 solution? [duplicate]

For the preparation of CaO NPs, how to remove NaCl formed after the reaction of CaCl2 and NaOH, since the resultant solution after the reaction is in liquid state. Also the precipitates contain only ...
27 views

### Gibbs energy of formation of DNA double strand [on hold]

in this example I do not understand why they use the delta seqG that they do. I.e. how do they sum the Gibbs energy for the given strand? Thanks for any help. and solution given: How does that ...
23 views

### Literature value for the activation energy of the reaction between hydrochloric acid and sodium bicarbonate

Does anybody have the literature value for the activation energy of the reaction between hydrochloric acid and sodium bicarbonate? If yes, could you please cite the source for it and the value? I ...
28 views

### CaO nanoparticles

I want to make CaO nanoparticles through the reaction between calcium chloride and sodium hydroxide but afterwards I want to remove NaCl from the reaction mixture.Please if anyone knows the procedure?
198 views

### Representation of bromelain molecule in two dimensional diagram [on hold]

If I'm not wrong, I learned in 2011 introduction to neuropsychology course that all enzymes are proteins. As far as I know, any protein, not even the smallest of the TAL group (which I understand to ...
30 views

### Purity of aluminium and experimental setup differences between Hoope and Hall–Héroult processes

Recently I was taught how aluminium is commercially extracted. The ore is first concentrated by leaching either by Bayer's process for red bauxite (impurity: $\ce{Fe2O3}$) or by Serpeck's process for ...
12 views

### Can triethylene glycol be used to remove polypropylene from the die during the glycol bath process?

We use the glycol bath die cleaning process in order to clean our die which are used to extrude materials from PBT and PET. Can triethylene glycol be used in order to clean a die containing ...
18 views

### how to test for purity [on hold]

Is there a home testing method for the purity of lgd4033? Formula: C14H12F6N2O IUPAC ID: 4-((R)-2-((R)-2,2,2-trifluoro-1-hydroxyethyl)pyrrolidin-1-yl)-2-trifluoroMethyl)benzonitrile Elimination half-...
26 views

### Which is more stable , a phenyl carbanion or a ethyl carbanion? [on hold]

I came across this question in my class test and the answer given is ethyl carbanion . But as per the S character and electronegativity , the phenyl carbanion should be more stable . My teacher told ...
44 views

### Why does snow sublime even when the surrounding temperature is below 0 °C?

Snow in winter below 0 °C, still sublimed very slowly over time. If I’m not mistaken, sublimation is an endothermic process. Where is this absorbed energy coming from when the surrounding temperature ...
21 views

### Enthalpy Changes [on hold]

0.50 g of Mg is added to a 50 mL HCl solution. The temperature increased by 5.2 degree Celsius. Calculate the enthalpy change for the reaction per mole of Mg that reacted.
48 views

### Which of the following isomers of 2,3‐dihydroxy‐4‐methoxy‐4‐oxobutanoic acid are identical?

Which of the following are identical? A and B are identical A and B are diastereomers A and C are enantiomers A and B are enantiomers What I know is that when we rotate a ...
43 views

### If water freezes at 32 °F (0 °C) at sea level, then what temperature does ice melt? [on hold]

If water freezes at 32 °F, what happens to that newly formed ice at that temperature? Does it start melting as soon as it’s frozen, or does it require more heat to melt again? If it does require more ...
110 views

### How is Zn not a transition metal? [duplicate]

A transition metal can be defined as an element that possesses an incomplete sub-level in one or more of its oxidization states. In the textbook I'm reading, it claims that zinc is not a transition ...
15 views

### Salt recovery from brine solution

I have a solution of brine (NaCL) which after passing in to multiple effect evaporator its become saturated and some crystalline. We pass that solution in the centrifuge to recover salt but the ML ( ...