All Questions

1
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0answers
18 views

Using Wilkinson's Catalyst to reduce esters?

I was solving some questions on alcohols when I came upon a question in which it was asked that whether esters can be reduced using hydrogen in the prescence of wilkinson's catalyst. Now I know that ...
3
votes
1answer
138 views

LDA and an aldehyde

Compounds A and B both react with LDA (lithium diisopropylamide, a strong base) to form the same anion C with the formula $\ce{C4H5O^-Li^+}$. I am unfamiliar with LDA. My first thought was that ...
-3
votes
0answers
12 views

Using Hess's Law [closed]

Calculate ΔH for the reaction 2 Al (s) + 3 Cl2 (g) → 2 AlCl3 (s), given: a. 2 Al (s) + 6 HCl (aq) → 2 AlCl3 (aq) + 3 H2 (g) ΔH = -100.8. kJ b. HCl (g) → HCl (aq) ΔH = -69.7 kJ c. H2 (g) + Cl2 (g) → ...
-1
votes
0answers
19 views

Theoretical Resistance Relationship of Electrolytes [closed]

I'm a senior physics/chemistry student working on a practical assignment where I am trying to identify the resistance of CuSO4 in solution (distilled water). I have recorded my data and determined it ...
-1
votes
0answers
34 views

Which of the following are correct about cycloalkane stability? [closed]

Which of the following are correct about cycloalkane stability? A) Stability ∝1 anglestrain B) Stability ∝1d where d is distortion or deviation from 109°5' for 1 bond C) Stability ∝1 ...
-1
votes
0answers
15 views

Does electron affinity affect bonding [on hold]

I know the Enthalpy for the first electron affinity will be negative, but what happens when an atom bonds with two other atoms and gains two or more electrons? What happens then?
1
vote
1answer
40 views

Lewis structure of benzenediazonium [closed]

In the benzenediazonium $\ce{C6H5N2+}$ the nitrogen contributes its lone pair to the carbon in benzene. So where is one electron of that carbon, since it is not used for bonding with nitrogen where ...
2
votes
1answer
67 views

Gibbs Free Energy and Maximum Work

I am a high school student and my professor mentioned that the Gibbs free energy is the maximum amount of work (or useful work) that a system can do, whereas entropy is a measure of the non-available ...
-1
votes
0answers
23 views

Product of 2,4-Pentanedione and PFBHA Reaction [closed]

I have made a solution derivatizing 2,3-Pentanedione with PFBHA. I am trying to figure out the product I have made. I know the chemical formula is C5H8O2 for 2,3-pentanedione and C8H4F5NO for the ...
26
votes
2answers
6k views

When a candle burns, why does the top of wick glow if bottom of flame is hottest?

Totally an elementary question. Staring at a candle, it appears that the bottom of the wick is dark whereas the top glows. However the bottom of the flame (the blue) is the hottest. Is the reason ...
0
votes
0answers
16 views

Effect of Concentration on Reaction Rate - Calculating Final Concentrations in Solution [closed]

Question asks: Determine the final concentration of IO₃⁻ used in the reaction. Show a complete sample calculation for the (8.0 mL Solution A + 2.0 mL H2O Equation: IO3− + 3HSO3− → I− + 3 HSO4− ...
-2
votes
0answers
10 views

Ingredient mixing [closed]

what ingredient (when mixed with liquid i.e juice etc...) will help to preserve candy (gummy and hard)? It also has to be non toxic because it is being ingested. It also has to go along with syrups.
0
votes
1answer
52 views

Why do metals form cations?

metals that have a low number of occupied shells such as lithium and potassium should have a stronger electrostatic attraction to their nuclei, so what causes them to always lose their electrons ...
-4
votes
0answers
27 views

Reactions to Caffeine [closed]

I am looking to see what reacts with caffeine for a school project. I wish to not go too far into detail, seeing that I am trying to invent something to better medicine with, but any information would ...
-3
votes
0answers
23 views

Calculating Volume of CO2 produced [closed]

The question states "What volume of CO2 will be produced if you react 1.5 g of Li2CO3 with an excess of 6.0 M HCl at room temperature?" Which fundamental equations could be used to solve such a ...
1
vote
1answer
40 views

CIP Rules - How to deal with a double bonded nitrogen? [on hold]

If a substituent were to exist, how will one deal with the doubly bonded nitrogen? In the tree will the nitrogen with the double bond have (C,C) or (C,C,C) or (C,C,lone pair)? I could not find this ...
0
votes
2answers
45 views

Size of hydrocarbons and boiling point

Increasing the contract surface area between hydrocarbons raises boiling point, so hexane should have a higher boiling point than propane. This doesn't really make sense to me. What is the difference ...
-2
votes
0answers
26 views

What effect do Bond angles have on molecules? [closed]

What are examples of the effect of different types of bond angles between different molecules and between same molecules with different Bond angles?
2
votes
0answers
69 views

Importance of substrate stereo chemistry in semi pinacol rearrangement [closed]

Consider the following two reactions (source): I don't quite get why the products shown are the main ones. In reaction 3A., if you rotate the carbon facing us by 120 degrees clockwise, the anisole ...
1
vote
0answers
18 views

Final product when sp2 oxygen of acid is O18 in fischer esterification

In the question above, i was curious about option 3. If the carbonyl oxygen is O18, shouldn't half of the product we obtain contain O18 on the carbonyl since we have two possible leaving groups with ...
3
votes
2answers
258 views

Why is my conclusion inconsistent with the van't Hoff equation?

Let's say I hypothesize that a graph of $\ln K$ vs. $1/T$ has a slope of $-∆G^\circ/R$ and a $y$-intercept of $0$. I prove it simply: $$∆G^\circ = -RT\ln K \quad\to\quad \ln K = -\frac{∆G^\circ}{RT}$$...
0
votes
0answers
19 views

Hydrogen peroxide and carbon as hybrid rocket propellant?

I was thinking that a hybrid rocket could be made using hydrogen peroxide and activated charcoal or some other carbon source. Step 1: Decompose hydrogen peroxide to steam and oxygen, as in a ...
-1
votes
1answer
26 views

Could there be a class of drugs beyond, similar to barbiturates and benzodiazepines? [closed]

I'm talking about group of drugs similar to them but different though.Is there anything beyond benzodiazepines?
0
votes
0answers
16 views

Basicity of subsituted amines

In comparing hydroxylamine, hydrazine, and methylamine for basicity, the order of increasing basicity is hydroxylamine < hydrazine < methylamine. I tried to reason this trend based on electron ...
-1
votes
1answer
55 views

What happens in this reaction! Some hints needed

I understand step A involves reductive ozonolysis. and that step B is addition involves addition of ammonia to the carbonyl site to form imines. But what does the sodium salt of trichloroacetic acid ...
0
votes
0answers
14 views

Is the exchange interaction always less in value than coulomb interaction? (Absolute values of both.)

I wonder for 2 electron interactions whether exchange interaction (K) is always less than the coulomb interaction(J) value in all cases (HF or DFT) or there is no such necessity? Does it depend on the ...
1
vote
0answers
24 views

Why can't a thermosetting plastic be stretched like an elastomer?

So far I've learnt that there are 2 'types' of thermosets: thermosetting plastics and thermosetting elastomers. Both of them consists of crosslinks that when stretched, allows for the material to ...
-1
votes
0answers
20 views

Neighbouring Group Participation [closed]

Usually in organic chemistry i have learnt that the more stable the intermediate, the faster the product formation. But in neighbouring group participation don't we get three or four membered rings ...
2
votes
1answer
25 views

notation on MO diagrams

I wanted to ask a question about notations on MO diagrams. Our first lesson about MO diagrams was today and I was taken through an example with $\ce{F2}$ as shown below: but one thing that the ...
1
vote
0answers
45 views

Why do tetrahedral organic molecules show stereo-isomerism, but not tetrahedral transition metal complexes?

Both types of molecules show different arrangements of the molecule in space, so they should qualify for optical isomerism right?
1
vote
1answer
41 views

Why do some ions form tetrahedral complexes more readily than others? [closed]

Why does Co$^{2+}$ readily form tetrahedral complexes such as [CoCl$_4$]$^{2-}$, whereas Fe$^{2+}$ usually forms octahedral complexes?
0
votes
0answers
36 views

Will evaporation from two immiscible liquids blow up a balloon?

Consider the following setup: Two immiscible liquids A and B are placed inside a balloon at a temperature where neither one of them boils. The inside of the balloon contains some argon, and the ...
-2
votes
0answers
47 views

Does this ring expand in this situation? What's the mechanism behind this? [closed]

So this is picture that sketches the situation. [EDIT] Thanks @glucose for putting me back on the rails. To wrap this all up and complete this topic, the answer to my question should be the product ...
8
votes
0answers
38 views

Disproportionation of Au(II)

Cu(II) and Ag(II) complexes are known to exist while Au(II) is unstable and disproportionates to Au(I) and Au(III). My guess as a possible reasons to this effect is that Au(II) like Cu(II) and Ag(II) ...
1
vote
2answers
79 views

Why is reduction potential of water ( 2H₂O + 2e⁻ → H₂ + 2OH⁻ ) is -0.83 insted of 0, as in the case of (2H⁺ → H₂)?

I came across this value of reduction potential of water while solving a question. Also, I noticed that, for example $$\ce{Ag+ → Ag}$$ has a fixed standard potential, and the same is used when we do ...
1
vote
1answer
25 views

Diluting a sample of weak base before titration. What happens to equivalence point pH of diluted vs undiluted?

A student titrated a 10.00 mL of 0.20 M methylamine ($\ce{CH3NH2}$) and determined that 10.00 mL of $\ce{HCl}$ was needed to reach the equivalence point. If you diluted your original sample of ...
2
votes
1answer
35 views

IUPAC Recommendations for Concentration Units (ppb, ppm)

In a recent interesting post, (Is 1 ppb equal to 1 μg/kg?) it was pointed out that IUPAC advises to abandon parts per million, parts per billion quantities and instead it suggests to employ micromole/ ...
7
votes
2answers
160 views

Cp vs Cv for liquid water @ < 4 °C

I'm looking at a textbook question (Engel & Reid, Thermodynamics, Statistical Thermodynamics & Kinetics, 4 ed, Q3.1) which states the following: The heat capacity $C_{\mathrm m,p}$ is less ...
0
votes
2answers
36 views

Borane as a reducing agent

I understand that adding borane to an alkene will produce a hydroborane. Addition of -OOH will form an alcohol. My lecture notes state that addition of borane to: A carboxylic acid will form an ...
-1
votes
1answer
60 views

Is it safe to boil carbonated water in a kettle? [closed]

Isn't it dangerous to boil carbonated water in a kettle? Whenever I boil water in my kettle, I close its lid. Does this close lid constitute 'under pressure' (and so danger) emboldened beneath? ...
21
votes
2answers
3k views

Storing hydrofluoric acid before the invention of plastics

The first person to synthesize hydrofluoric acid in large quantities was Carl Wilhelm Scheele in 1771. This acid is known for its ability to corrode glass and metals. What materials were the ...
-2
votes
0answers
24 views

Formula Issue: At what relative concentrations of Pb2+ and Cd2+ will these half-reactions have the same reduction potential 25 degrees Celcius? [closed]

Standard reduction potentials for the Pb2+/Pb and Cd2+/Cd half-reactions are −0.13V and −0.40V, respectively. This is the question, I’m just confused on which formula should be used. E=E^0-(0.0592V/n) ...
0
votes
1answer
34 views

Calorimetry: Temperature Increase due to stirring of reactants

I am not yet in university, but I hear a common first-year chemistry lab/practical is to do calorimetry taking into consideration the small (and usually negligible) rise in temperature due to the ...
1
vote
0answers
85 views

Would burning of around 200 kg of animal fat in a tunnel cause an explosion? [closed]

As shown in the movie Ironclad, they burnt a group of fat pigs together, under a tunnel, beneath the fort base and it resulted in a massive explosion. From chemistry's perspective, and considering ...
0
votes
1answer
19 views

Precipitation of Cu2+ and Pb2+ ions

Hi chemistry enthusiasts! I am working on my scholarship exam practice. I believe this exam assumes high school + first year university knowledge although the standard may be varied across the world. ...
-1
votes
0answers
17 views

Interaction in capsule between resveratrol, berberine, nicotinamide, astaxanthin? [closed]

I would like to know whether mixing Trans-Resveratrol 98%/C14H12O, Berberine HCL (hydrochloride)/C20H19ClNO4, Nicotinamide (vitamin B3)/C6H6N2O, and Astaxanthin/C40H52O4 in a capsule without any ...
2
votes
1answer
32 views

Change in Gibbs free energy vs. change in enthalpy

When learning about other thermodynamic quantities, like $\Delta H$, I was taught that this represents the energy absorbed or released by a system after the reaction has gone 100% to completion. For ...
3
votes
2answers
45 views

How fast is the interconversion triplet → singlet in organic molecules?

When computational studies are performed on transition state geometries, the "thermodynamic" (that is, with no kinetic considerations) energy of the analyzed state is obtained. I was wondering: if a (...
2
votes
1answer
44 views

Can glucose and insulin exist in the same container without reacting?

Someone asked if glucose and insulin could be mixed in the same container and used as an injection to provide a quick energy boost. I'm not interested about the medical part of this question, but just ...
3
votes
2answers
48 views

Precipitating silver(I) salts from the solution of barium(II) cyanate and iodide

Consider a $\pu{10.0 mL}$ solution containing $\pu{1.0e-10 M}$ each of $\ce{Ba(CN)2}$ and $\ce{BaI2}$. If $\pu{3.5e-9 mol}$ of $\ce{AgNO3(s)}$ is added to this solution, will any precipitate(s) form? ...

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