# All Questions

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5 views

### Which salts give the sodium carbonate bead test?

Apart from the borax and the phosphate bead tests, there's also this one. It's done by heating the white bead of sodium carbonate and the salt with potassium nitrate; green and yellow colours ...
19 views

### Why is benzene more aromatic than naphthalene and anthracene?

Though all three Anthracene, Naphthalene and Benzene are aromatic, why is benzene considered the most aromatic? What determines the strength(degree) of aromaticity? How do we determine the strongest ...
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### Does lead carry the negative charge in plumbane?

It says in Wikipedia that lead tetrahydride or hydrogen plumbide or plumbane (PbH4) is supposed to have lead in it's -4 state and the hydrogen is in its +1 state because supposedly lead has a higher ...
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### What product is created in a zinc - nitrate reaction?

From the question "Place 2 mL of Nitric acid in a test tube and add a small piece of Zinc turning" I thought that the overall net ionic equation would be Zn + 2H+ --> Zn2+ + H2 Is this ...
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### Acidicity and anion stability across periods and groups of the periodic table

I understand that to compare relative acidity one must consider the stability of the conjugate bases. Across a period the electronegativity of an element increases. And that is for example why HF is ...
19 views

### How can I set up and process my Excitation-Emission matrices properly?

I'm running EEMS on some water samples on a Horiba Fluoromax 4 spectrofluorometer. Method below. 240-580nm emission, 5nm interval, 1nm width 240-480 excitation, 5nm interval, 1nm width 0.01 mg/L ...
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### My EDTA titration isn't giving the right titre

I am, as a fun off-syllabus investigation, looking at hard water and how effective the EDTA titration method is, for permanent and temporary hard water. I ran a titration today and had horrific ...
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### Protocol on gel shrinkage (water loss)

Would like to ask if you can hit me up with some sources or link or suggestion for a protocol that would evaluate gel shrinkage. This is a gel that decreases irrigation flow and after the test, we ...
25 views

### Does increasing energy lead to Bigger size of orbitals?

I am a Beginner in Learning Atomic structure and I am getting confused at Aufbau's principle For instance,Let us consider the example of atom's electronic configuration It is stated that the electrons ...
27 views

### Diastereomers - cyclic compounds

Why in this problem there isn't a diastereomer with the $\ce{-CH3}$ in the back (dash) and the $\ce{-CH2CH3}$ in front (wedge)?
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### Why a single covalent bond is stronger than a single ionic bond? [closed]

As explained by my teacher a single ionic bond is always weaker than a single covalent bond. Due to lattice formation the ionic compounds have high melting point and boiling point. Is it beacuse ...
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### combination of H2 and O2 after electrolysis [closed]

if we electrolysis water in a closed container H2 and O2 is formed, now as the container is closed both gases remain there when the electrolysis stop and water cool down will h2 and o2 remain in the ...
42 views

### Finding the pOH of a buffer from the scratch without the Henderson Hasselbalch equation

I found this question on the internet that said: Find the pOH of the solution obtained by mixing $\pu{0.1 mol}$ of $\mathrm{NH_4 OH}$ $(K_\mathrm b = 10^{-5})$ and $\pu{0.1 mol}$ of $\ce{(NH4)2SO4}$ ...
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### Can any one list the set of fundamental unsolved questions in coordination chemistry? [closed]

I am interested in unsolved problems in coordination chemistry, from particular cases to the most fundamental phenomena. Thanks in advance
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### What does fractional notation represent in molecular formulas such as SiO4/2 or H2SiO2/2?

I'm going through some papers about HSQ (hydrogen silsesquioxane) and keep seeing this fractional notation being used: HSiO3/2 , SiO4/2 , H2SiO2/2 , H3SiO1/2. Example paper. I understand that the ...
22 views

### Why is ethanol, water and amonium needed for DMG to react with nickel?

I had this question on a test and I'm unsure on why ethanol is required for the reaction. I understand that you need the ammonia and water to make oxonium ions needed for the reaction to occur. We had ...
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### Is the effective nuclear charge only defined for valence electrons?

I've just been taught about the effective nuclear charge and screening effect in school. I'd like to ask and confirm if the effective nuclear charge is only defined for valence electrons. If not then ...
37 views

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### Finding major product after dehydration

here,should I prefer hydride shift or a product with more $\alpha$ hydrogens? my doubt is...as hydride shift is easier than methyl shift,the answer should be $a$ or $c$.if methyl shift takes place the ...
23 views

### Can we create metals and/or elements artificially, sufficiently enough to replace or eventually replace mining?

Before you answer the question, please note I am not a chemist or a physicist, I'm simply curious. My question is in the context of scarcity. Is it possible to artificially create materials such as ...
19 views

### How to compare volatility of inorganic acids

Extending This question further Sulfuric acid because of its low volatility can be used to manufacture more volatile acids from their corresponding salts To use this statement in practice I need to ...
12 views

### Electron configuration using periodic table [closed]

I need to find electron configuration for an element beyond 118 (I don't want to tell the element's atomic number 'cause I need to find the electronic configuration). I'm able to find electronic ...
22 views

### Confusion regarding Finkelstein Reaction

In Finkelstein reaction we know when a primary alkyl chloride or bromide is treated with NaI in acetone, we get the corresponding alkyl iodide Now acetone is a polar aprotic solvent and order of ...
20 views

### Does dissociation produce a mixture? [duplicate]

I was wondering why a a salt that dissociates in water will be a mixture? The definitions for a mixture says that "Components do not chemically react with each other." Isn't dissociation ...
36 views

### Which has maximum number of oxygen atoms? (A) 1 gm of O (B) 1 gm of O2 (C) 1 gm of O3 (D) All have same no. of O-atoms [closed]

Which has maximum number of oxygen atoms? (A) 1 gm of O (B) 1 gm of O2 (C) 1 gm of O3 (D) All have same no. of O-atoms Please explain with the reason !
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### Phenolphthalein + sodium carbonate and phenolphthalein + sodium bicarbonate [closed]

What would the word equations be for the following two situations? Initially $\ce{Na2CO3}$ and $\ce{NaHCO3}$ were present as 2 unknown powders, dissolved in water, and phenolphthalein was added to ...
20 views

### Why does increased conjugation in a molecule cause the wavelength absorbed to decrease (i.e. why does a red-shift occur)?

I was recently looking at a paper about novel organic dyes for efficient dye-sensitized solar cells and one point the authors made was that out of the two dyes mentioned the one with a larger pi-...
44 views

### Using symmetry and group theory arguments to explain iron(II) in a tetrahedral crystal field

I am trying to figure out how to explain $1s \rightarrow 3d$ spectroscopic transitions for $\ce{Fe^{2+}}$ in $T_\mathrm{d}$ symmetry. These transitions make up the pre-edge region in K edge X-ray ...
16 views

### Le Chatelier’s Principle chem [closed]

How would I answer a question like this on a test? Removal of one of the products of a chemical reaction has the effect of causing the reaction to go to completion. Explain this in terms of Le ...
31 views

### Synthesis of 1-naphthaleneacetic acid: Methods

I am trying to synthesizing 1-naphthaleneacetic acid from naphthalene and monochloroacetic acid. I found some patents and papers, and I have tried to synthesis but the yield is low. I used iron powder ...
28 views

### How to write the Nernst Equation for this reaction?

I am required to write the Nernst equation for the following reaction: $\ce{O_2 + 4H^+ + 4e^- -> 2H_2O}$ Clearly, here $\ce{O_2}$ is getting reduced from an oxidation number of zero to an ...
29 views

### I need to find the mechanism of a reaction [closed]

As in the title, I have a reaction to witch I need to give the mechanism.
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### Why is F a bad leaving group? [closed]

Why is F a bad leaving group? I thought that a good leaving group is one that tends to leave easily (=strong acid or weak base) and is stable (ergo a weak base or a strong acid). So wouldn't F be a ...
26 views

### Which human protein is the most expensive energetically for the human body to create? [closed]

The human body contains between 80,000 and 400,000 different kinds of proteins. Which protein or class of proteins requires the most energy to produce?
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### Could ammonium phenolate be merely a solution of ammonia in phenol?

Could ammonium phenolate be merely a solution of ammonia in phenol? Ammonium phenolate (or phenoxide) is a liquid with a CAS number, 5973-17-1, and boiling point of 181.8$^o$C http://www.chemnet.com/...
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### Why does calcined feldspar crumble?

For context, I am a potter and am interested in collecting and processing all materials that I use by myself. One of the processes which I use is calcination of certain minerals like feldspar, so that ...
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### Le Chatelier’s principle Chemistry question [closed]

In caves we sometimes see large structures known as stalactites and stalagmites. These formations are made of crystals of the insoluble compound calcium carbonate, CaCO 3 (s), also known as limestone. ...
21 views

### Volume percentage [closed]

When we say that nitrogen occupies 78% , oxygen 21% and other gases 1% by volume of the total volume of air, what do we actually mean by it? I am confused because I have been told that molecules of ...
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### Mechanistic detail for Dehydration of benzaldoxime with acetic anhydride reaction [closed]

Please draw out and explain the mechanism for Dehydration of benzaldoxime with acetic anhydride rection. I'm struggling to find anything about it. Thank youuu :)
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### Titration of weak acid and strong base at low concentrations [duplicate]

Titration continues until one of the reactants (the one in conical flask) turns out to be a limiting agent as far as I know. From the titration of a weak acid and a strong base, I could learn that the ...