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9 views

Acid-Base Titration: Calculate moles of acid and salt at equivalence point [closed]

Harry was given a sample of an unknown acid, HA(aq), with an unknown concentration and unknown volume, and it was titrated with 0.100 M NaOH(aq). Instead of using an indicator, Harry measured the pH ...
-2
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0answers
11 views

Weak Base and Strong Acid Neutralization

Sodium bicarbonate, NaHCO3, is a weak base that is commonly used to neutralize acid spills. Explain what will happen to the pH of a solution of 0.10 M NaOH(aq) after a small amount of sodium ...
0
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0answers
4 views

How to convert 3.15 mg/ml stock to 200 ng/ml in total 200 ul water solution and make it pipettable? [closed]

I have 3.15mg/ml of a standard antibody, I need to make it 200 ng/ml in total 200 ul with another liquid
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0answers
15 views

Can the expression be represented as a total differential?

I should determine whether the following expression represents a total differential: $$\mathrm{d}f(x,y) = (\ln y) \,\mathrm{d}x + \frac{x}{y}\,\mathrm{d}y$$ But with the following method (physical ...
-1
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0answers
22 views

What are some very soft metal alloys? [closed]

Specifically, I wonder what the softest alloys containing aluminum, tin and/or zinc are. How does one predict the properties of such alloys? Does the combination of two soft metals equal the creation ...
-1
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1answer
24 views

Why doesn't tetrachloromethane react with aqueous sodium hydroxide under reflux?

$\ce{CCl4}$ does not react with hydroxide nucleophile whereas $\ce{CH3Cl}$ does. I had initially thought that it was due to symmetrical geometry of $\ce{CCl4}$ and so the dipoles cancel out and the ...
-1
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0answers
15 views

showing that two halide ions are in the same solution [closed]

Suppose you were to have a solution containing both iodide and chloride ions(found a question in a past paper similar to this one, but couldn't figure it out).. how would you show that the solution ...
-1
votes
1answer
28 views

Calculation of hypochlorite concentration from active chlorine

So in the lab we got sodium hypochlorite solution. The concentration is in active chlorine (13%) on the label. How do I calculate it to concentration of hypochlorite? I need certain amount of ...
-1
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0answers
24 views

Why do Ferrocene and Nickelocene vary in their properties even though they're similar in structure? [closed]

Got this practice question for my finals but have no clue where to start. Could someone please help answer this? "Ferrocene and Nickelocene are similar in structure but vary in their properties. ...
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0answers
31 views

HCl added to water

Suppose we throw $\ce{ΗCl}$ inside a container full of $\ce{H2O}$. This reaction takes place. $\ce{HCl + H2O -> Cl- + H3O+}$ for each molecule of $\ce{HCl}$ added to water Now both $\ce{Cl-}$ and $\...
-1
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0answers
17 views

Why is Water added when determining peroxide value of oils [closed]

In the process of getting the peroxide values of oils following the standard AOCS method. An amount water is used after adding the KI and then finally followed by titration using sodium thiosulphate . ...
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0answers
21 views

How to make cypin? [closed]

I wanted to deaminate some Guanine I made, and for that I need Cypin. How do I make or extract Cypin? I want to make Xanthine using the Guanine.
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0answers
22 views

Electrophilic Aromatic Substitution on meta-xylene

During EAS on meta-xylene, is the product where the electrophile is added to the ortho position relative to both the methyl formed in good yield, since the methyl groups are bulky wouldn't there be ...
0
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0answers
17 views

Ionic radii of transition metal ions in the presence of weak field and strong field ligands

‎‎‎‎‎‎‎‎‎ In the graph given in this image,‎ I was told by my teacher‎ that whenever we start filling the eg orbitals there is an increase in the radius because these orbitals face the ligand directly ...
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0answers
37 views

Questions on Third Law of Thermodynamics

Third Law of Thermodynamics reads: at absolute zero , the entropy of a perfectly crystalline substance is zero. (https://simple.wikipedia.org/wiki/Third_law_of_thermodynamics) And considering the ...
0
votes
1answer
30 views

Why is this graph of vibration spectroscopy like this?

This graph shows the absorbance of different wavenumbers of infrared radiation causing different forms of vibrations of the water molecule. I would like to know why the graph turns out the way it is. ...
-1
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0answers
20 views

Problem related to 5p orbital wave function describing them? [closed]

This question appear in our first year UG chemistry course. According to me first and last option are the correct. (According to material which were taught to us 2pz orbital can be completely ...
-1
votes
1answer
21 views

Degrees of freedom of a molecule of N atoms

Apparently a molecule of N atoms has 3N degrees of freedom. How? Shouldn't it be dependent on the structure of the molecule? How exactly do we derive this?
0
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0answers
21 views

Why are halogens discharged during the electrolysis of aqueous metal halides despite their high electronegativity?

The electrolysis of concentrated aqueous metal halides (such as $\ce{NaCl_{(aq)}}$) results in the halogen anion getting discharged at the anode, but why is this so? Since halogens like $\ce{Cl}$ are ...
-1
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0answers
23 views

Which hydrogen bond is stronger?

I'm designing an anion just for fun; as it turns out, it involves a double bond with one side being the CF3 group and the other side the SO3- group. This would make the anion chiral; both conformers ...
-2
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0answers
21 views

How do I answer this question? [closed]

A student performs an experiment several times to determine the enthalpy of combustion of naphthalene, an organic compound with the formula C10H8. The student collects the following data: −5182.6kJmol,...
0
votes
1answer
65 views

How to extract pure carbon dioxide from sodium bicarbonate?

What are the most commonly-used methods for extracting carbon dioxide gas from an aqueous solution of sodium bicarbonate? Several industrial "Carbon Capture" plants today are able to extract ...
1
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0answers
29 views

Can chloralkali process be used with ocean water to produce sodium hydroxide?

Are there any modern-day Chloralkali plants that create $\ce{NaOH}$ using water from the ocean? I'm trying to understand how modern-day plants that use the Chloralkali process to create $\ce{NaOH}$ (...
-2
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0answers
30 views

How can a voltage reading be converted into concentration of a solution? [closed]

I'm trying to construct an Arduino device that measures the concentration of salt ions in a saltwater solution. I've figured out how to take a reading of the voltage, but how can I (mathematically) ...
0
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0answers
17 views

Can we assume that the ionic bond equilibrium separation distance is simply the sum of the atomic radii?

Background I am reading a materials science textbook. The current section is discussing ionic bonds and the attractive/repulsive forces between ions. The attractive force between ions is given as $$ ...
0
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0answers
11 views

Why do silyl groups increase the acidity? [duplicate]

I don't understand how a silyl group can increase the CH-acidity. I know that a silicon in beta position stabilizes the carbocation because of hyperconjugation, but how can one explain the ...
0
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0answers
29 views

Relative Humidity inside a thermally insulated chamber for a NACL solution

I ran an experiment, where I had to measure the relative humidity of a thermally insulated chamber containing NaCl solution. I have read from a few papers, that the relative humidity of a NaCl ...
0
votes
2answers
25 views

How to make NaxPO4 buffer?

I am currently trying to make a buffer for protein expression. According to the article, I am to use a buffer with $\pu{50 mM}$ $\ce{Na_{x}PO4}$, $\pu{pH 8}$ (and $\ce{0.5 M NaCl}$). How do I make the ...
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0answers
23 views

vitamin D test in mushrooms [closed]

How could I test vitamin D levels in mushrooms? (I am a high school student, our lab is pretty modern, but not as fancy as colleges have). I need it to complete my extended essay experiment
3
votes
1answer
102 views

Why are 2D block matrices considered irreducible?

I am currently reading Applications of Group Theory by M.S. Dresselhaus On page 18 irreducible representations are defined and an example is given as follows: The author claims that these ...
0
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0answers
20 views

For Calcium and Potassium, as 4s is then lower energy than 3d,(and lower means or normally means nearer), would 4s thus be nearer the nucleus than 3d?

For Calcium and Potassium, as 4s is then lower energy than 3d, (and lower normally means nearer), would 4s thus be nearer the nucleus than 3d? For example. I read in the accepted answer to Why does ...
1
vote
1answer
44 views

Solid materials with dipolar molecules

I am trying to heat solids using controlled microwave radiation and I am therefore looking for materials that absorb microwaves well. I have understood understood that for radiation in the radio ...
-1
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0answers
10 views

Does atomic radius increase down a group due to the shielding effect, the increase in occupied energy levels, or both?

I understand that atomic radius increases down a group (of the periodic table) due to an increase in occupied energy levels, which puts the valence electrons in a higher energy level and further from ...
0
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0answers
64 views

Finding reaction equilibrium constant from Gibbs free energy and enthalpy

For the reaction $$\ce{3 Fe2O3(s) <=> 2 Fe3O4(s) + 1/2 O2(g)}$$ $\Delta_\mathrm{r}H^\circ(\pu{298 K}) = \pu{55.5 kcal mol^-1}$ and $\Delta_\mathrm{r}G^\circ(\pu{298 K}) = \pu{46.5 kcal mol^-1}.$ ...
-1
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0answers
32 views

How to synthesise 1,3-dioxo-1,3-dihydro-2λ^5-spiro[isoindole-2,1'-piperidin]-2-ylium? Does it even exist?

I saw some quite strange problems on my ochem exam. For instance, there was a question about this cation. I supposed that this is the way of 6-membered ring nucleophilic opening. But searching about ...
0
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0answers
38 views

How do you draw the pi MO diagram for the acetate ion CH3COO-

How do you draw the pi MO diagram for the acetate ion CH3COO- ? I get stuck with the number of electrons on the 2p orbital of Oxygen atom. My teacher said 1 oxygen has 1e, the other has 2e. But ...
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0answers
14 views

What should be the product of hydration of 1‐phenyl‐1‐propyne by Kucherov reaction? [closed]

What should be the product of hydration of 1‐phenyl‐1‐propyne by Kucherov reaction? $$\ce{Ph-C#C-CH3 ->[HgSO4][H2SO4]}$$
2
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0answers
31 views

Does red phosphorus with hydriodic acid reduce all alkyl halides?

$\ce{HI/P}$ is used for reduction of alcohols, aldehydes, ketones and acids to alkanes. As for alkyl halides, I have read that only alkyl iodides are reduced, whereas other alkyl halides do not: $$\ce{...
-1
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0answers
10 views

Percentage of mass in solution [duplicate]

What does the statement ‘2% solution by mass’ mean exactly? I’ve encountered this a couple times and am unsure of the meaning.
0
votes
1answer
38 views

Does a metal being "soft" equal being able to scrape onto paper?

When you scrape aluminum onto paper, it makes a faint mark. The question is, does softness of a metal correlate to how well a mark shows up when you scrape it onto a surface such as paper?
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votes
0answers
12 views

How to prepare 0.25M citric acid solution using citric acid monohydrate powder? [closed]

How to calculate the quantity of solute (citric acid monohydrate) required for preparing 0.25M citric acid solution?
2
votes
1answer
119 views

Complete mechanism of benzotriazole synthesis from o-phenylenediamine

Does my suggested mechanism for benzotriazole synthesis look correct? Are the arrows for the cyclization in the right place? Chemdoodle (which I drew this with) makes the curly arrows look a bit weird....
-2
votes
0answers
39 views

In the question given below based on the concept of Chemical kinetics

In the following reaction: $$\ce{N2(g) + 3H2(g) -> 2NH3(g)}$$ The rate of appearance of $\ce{NH3}$ is $\mathrm{d}(\ce{NH3})/\mathrm{d}t = \pu{1.7 kg/h}$. The rate of disappearance of $\ce{H2}$ will ...
-3
votes
0answers
19 views

Acids and Bases Buffer Solution Question Help [closed]

The question goes as follows: "Two solution of sodium acetate are prepared, one having a concentration of 0.1M and the other having a concentration of 0.01M. Calculate the pH values when the ...
0
votes
2answers
51 views

Burning wood with ammonium chloride

There is a method where you use a water solution of ammonium chloride to paint some pattern or write some text on a piece of wood and then blow on it with a heat gun. The result is that the pattern ...
-1
votes
1answer
25 views

Which theory could describe rate constant for photodissociation?

I am considering photodissociation reactions and want to find an appropriate theory to describe how one could determine the rate constant. I know RRKM theory is for unimolecular reactions but I have ...
2
votes
0answers
38 views

What is the difference between milk and cream that causes disparate result when freezing and thawing?

If you freeze milk and then let it thaw/melt again you just need to shake and it is more or less indistinguishable from unfrozen milk. That is not true for cream - after letting frozen cream (40 % fat)...
2
votes
0answers
37 views

Calculating internal energy of fragment from $D_0$, photon energy and interval energy + velocity of other fragment

I am trying to solve the following: We consider a photodissociation of a molecule into two fragments. The energy available to the products can be calculated from the bond dissociation energy and the ...
0
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0answers
33 views

Simultaneous electrolysis on applying a suitable amount of potential difference

This question was asked in the JEE in 2020: $\pu{250 mL}$ of a waste solution obtained from the workshop of a goldsmith contains $\pu{0.1 M}$ $\ce{AgNO3}$ and $\pu{0.1 M}$ $\ce{AuCl}.$ The solution ...
-3
votes
0answers
19 views

Stoichiometry help [closed]

The percentage composition of a compound is 79.9% copper and 20.1% sulfur. The mass of a sample of the compound is 160.0 g. What are the masses of the copper and the sulfur in the sample?

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