Questions tagged [stability]
Applied to a chemical species, the term expresses a thermodynamic property in reference to a standard, stating that one state is lower in energy than another. The tag should be applied to questions seeking answers with respect to the stability (or instability) of a certain chemical species, molecular entity and/or electronic structure. It must not be applied to questions about the reactivity of particular chemical species.
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What is that substance coming from tractor tire?
I have old tractor with Bridgestone tires. When I press a clean white tissue against the tire, a black spot show on the tissue. Is that substance carbon black and it’s harmful to soil?
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Which methoxy- and nitro-substituted azulene has the lower ground state energy?
My contention is that the first azulene structure, with the nitro group on the aromatic cyclopentene ring has a lower ground state energy, as the negative charge can not only resonate into the nitro ...
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Is it possible to have multiple nitrogen atoms bonded to one carbon atom?
So I was wondering, if we replaced two of the hydrogens in methane with amine groups, would it be a stable compound? What about for R groups of varying size?
Similarly, if I tried to make a compound ...
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Why is silver(I) phosphate so unexpectedly thermally stable?
Silver(I) oxide is completely decomposed in air already at $\pu{300 °C}.$
Formulate the decomposition reaction and the corresponding mass action expression.
$\ce{Ag3PO4}$ can be melted at $\pu{800°C}$ ...
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Why are p orbitals most important for stability? [closed]
Is there nice way to see/show/derive why p orbitals are so important for stability? Or asked differently: Why are elements with filled p orbitals on the right side of the periodic table? Why aren't ...
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Organic solvents distillation for purification
I've realised that the majority of the solvent that we use in my lab are contaminated with grease (peaks at 1.26 and 0.86 ppm in $^1H$ NMR in $CDCl_3$), since they come in plastic containers (I guess ...
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NIST SRMs: Determination of the Validity Period
The National Institute of Standards and Technology (NIST) produces Standard Reference Materials (SRMs) of basically anything. That also means that things like peanut butter are among those SRMs. SRMs ...
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Does resonance stablization of carbocation increase ease of $\ce{S_N1}$ reaction or decrease it due to delocalization?
(A)
(B)
In both of the cases when a nucleophile approaches for $\ce{S_N1}$ reaction a carbocation is formed in place of $\ce{Cl}$ atom. I know that the rate of $\ce{S_N1}$ increases with increase in ...
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Stability of beryllium isotopes
I have been reading about isotopes and their abundance on Wikipedia. It states that lithium has 2 stable isotopes, beryllium has 1 stable isotope (monoisotopic and mononuclidic) and boron has 2 stable ...
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How long can a silicone and white spirit solution be stored without hardening?
I’ve heard that some people use a mixture of silicone and white spirit to waterproof their gear.
How long this solution can be stored without hardening if it is stored in a closed hermetic bottle?
If ...
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Stability of benzyl free radical hyperconjugated with a methyl group
In this picture, which one is more stable?
My teacher says the second one as it has 4 alpha-Hydrogen whereas in the first picture the free-radical carbon has only 1 alpha-Hydrogen. That's why second ...
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Why is anhydrous trans-Bis(glycinato)copper(II) more stable than it's cis isomer?
As is shown in Ref.1, the trans isomer is much more stable, at least at molecular level.
Based on the crystal structural data from Ref.2 and atomic radii of O and N from wikipedia and some little ...
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Stability comparision between cyclopropylmethyl and other stabilised cations?
So I had a test recently where this following question came
I don't have any concern with (1), there is no doubt in it. But, how do we tell the stability between (2), (3) and (4). Our sir said that ...
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Stability of different tautomers of vitamin C
Above all four tautomers represent Vitamin C (Ascorbic acid)
So here are some basic rules that I learnt.
1.Usually keto form is more stable due to bond enthalpy considerations
2.Enol form is stable if ...
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Stability of hexazine
I read about a hypothetical compound called hexazine on Wikenigma. It's a 6-membered ring all of whose atoms are nitrogen and they form alternate single and double bonds just similar to benzene. But ...
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Is there an international standard for rating the danger of chemical elements?
I'm writing a small little tool (something like an interactive periodic table) and I wanted a good "guesstimate" of the danger of certain elements, to visualize across said table.
I could go ...
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Why is water present in "pure" nitric acid and RFNA and WFNA?
Various types of nitric acid have been used in rocket fuels as oxidisers (RFNA is red fuming nitric acid, WFNA is white fuming nitric acid) as they are often hypergolic with a wide variety of fuels.
...
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Are mixtures of finely ground solid fertilizer compounds stable? [closed]
If I had a combination of the following as finely ground powders, would it be relatively stable, or would they react to form other compounds?
Sodium Nitrate
Ammonium Nitrate
Calcium Nitrate
Potassium ...
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Why is the reaction rate of tert-butyl chloride solvolysis faster in 80% water/20% acetone, than in 70% water/30% acetone?
The solvent is polar protic, so the mechanism is SN1. However, I don't understand how the composition of water and acetone in the solvent affects the reaction rate.
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What happens when iron(III) chloride is dissolved in ethanol?
I dissolved $\pu{25 mmol}$ $\ce{FeCl3*6H2O}$ in $\pu{25 ml}$ ethanol and got a clear ethanol solution of $\ce{FeCl3}$ 4 days ago. And I keep it in a drawer from light these four days.
However, when I ...
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Does germanium(IV) chloride have to be handled under inert atmosphere?
I am finding conflicting information on the proper handling of germanium(IV) chloride. Is the liquid air/moisture sensitive? Does $\ce{GeCl4}$ have to be handled in a glove box?
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Why does chlorine displace bromide
Found that chlorine will displace bromide, and iodide from their ion forms. According to my textbooks, this is because chlorine is more electronegative than bromine and iodine. However, the chloride ...
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Store Palladium Chloride in Solution
I have one gram of palladium chloride ($\ce{PdCl2}$) and I want to use very small quantities of it, in milligrams somewhere. It is not possible for me to get my hands on a scale that can measure that ...
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Which Group 16 elements form stable dihalides?
My textbook says that "except oxygen, all elements of group 16 form dichlorides and dibromides", while other sources quote that only Oxygen and Sulphur form dihalides and dibromides.
Whereas,...
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Why and how do aqueous silica systems precipitate and can its occurrence be mitigated by quantifying its speciation correctly?
Background/Context:
For context, I have been doing a lot of work on experimental systems in geopolymer chemistry lately with a focus on "activator" solutions which are essentially mixtures ...
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Why the electronic configuration of samarium is ending with 4f⁶6s²
What is coming in my mind is that 4f^7 6s^1 should be more stable as it allows two orbitals to be half filled rather than 4f^6 6s^2 in which only one orbital is completely filled....can someone please ...
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What makes a compound high or low energy and why does that relate to reactivity? [closed]
After reading about thermodynamic stability, it now makes sense to me how the enthalpy of a reaction relates to the thermodynamic stability of a compound.
However, when looking for a clear way to ...
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How specific is the exception of negative charge location (orbital vs atom) for determining stability of conjugate base?
Chapter 3 Acid-base reactions in Klein's Organic Chemistry As a Second Language explains an exception to the typical order of important factors for determining how stable a negative charge on a ...
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Stability comparison of europium(II) and ytterbium(II) ions
“Which one of the lanthanoids given below are most stable in divalent form?” This question was asked in JEE Main 2022 (Indian entrance test for engineering). Now the question had both $\ce{Eu^2+}$ and ...
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Why isn't formyl chloride stable? [duplicate]
I am currently studying methods of synthesising ketones and aldehydes and one of the methods is Friedel-Crafts acylation. However, my teacher told our class that we can't use this to make benzaldehyde ...
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Comparing reactivity of 3-bromocyclohexa-1,4-diene and 5-bromocyclohexa-1,3-diene towards SN1 reaction
Compare reactivity of 3-bromocyclohexa-1,4-diene (P) and 5-bromocyclohexa-1,3-diene (Q) towards $\mathrm{S_N1}$ reaction.
My teacher claims that the reactivity of P is more than that of Q. He ...
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Reactivity vs Stability: Chlorine Trifluoride
Chlorine trifluoride shows up on many pop science content, which is how I learned about it just today, as an incredibly reactive compound capable of oxidizing seemingly incombustible substances (glass,...
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Has tellurium(II) iodide been properly characterized ever?
According to Wikipedia, tellurium tetraiodide decomposes on heating:
$$\ce{TeI4 ->[\Delta] TeI2 + I2}$$
However, the reaction is somewhat wrong as according to this 2008 paper:
Solid tellurium ...
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What is the most stable cycloalkene? [closed]
I'm looking specifically at cyclopentene and cyclohexene. Supposedly, greater instability would lead to a more exothermic enthalpy of combustion. However, based on my data, cyclopentene is more ...
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Has a fully methylated pentagonal dodecahedrane been synthesized or at least attempted? If not, is there some reason it could not exist?
I first came across dodecahedrane in comments below What dodecahedral molecule is Linus Pauling likely holding in this photograph? Does it have 40 carbon atoms?
Wikipedia's Dodecahedrane; Derivatives; ...
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Dominance of electronic factors in cupric ion
I know that Cu+ ( cuprous ) ion is less stable than Cu²+ ( cupric ) ion . There are some reasons explaining this by high hydration enthalpies and low ionization enthalpies . Even though , these ...
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Why don't universal indicator solutions react with themselves?
Universal indicator is a pH indicator made of a solution of
water, 1-propanol, phenolphthalein, sodium hydroxide, methyl red, bromothymol blue, sodium bisulfite, and thymol blue
that exhibits ...
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How is propene more reactive as well as more stable than ethene?
I know that hyperconjugation stabilises a double bond. But in propene an electron-donating group $(\ce{-CH3})$ is increasing the electron density at the double bond, so its nucleophilicity should be ...
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Comparing stability of 1,3-dioxolan-2-ide and 1,3-dithiolan-2-ide carbanions
I'd like to compare stability of 1,3-dioxolan-2-ide and 1,3-dithiolan-2-ide carbanions:
I think there is no mesomeric or hyperconjugation effect and we should consider inductive effect.
Oxygen is ...
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How to remove graphite substrate of boron carbide coating?
I have a boron carbide coating (the thickness is either 90 microns or 220 microns) on a graphite substrate (the thickness is 0.5 inch - about 13 mm, the other dimensions are 2x2 inch$^2$ - about 5x5 ...
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Are there any organic compounds with three or more oxygen atoms bonded together in a straight chain?
Recently, there was a question which enquired about some oxygen rich compounds that burn themselves completely and thus not requiring any external atmospheric oxygen. The author came up with the ...
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Why can't the Fajans' rule and lattice energy theory be used to explain the difference in thermal stability of magnesium and calcium carbonates?
$\ce{CaCO3}$ is more thermally stable than $\ce{MgCO3}.$ I do understand that a larger cation would be able to stabilize a larger anion to a greater extent, but why can't we use Fajans' rule or ...
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Why is a branched alkane more stable than the straight-chain isomer?
My text book says that branched alkanes are more stable than their straight-chain isomers, but does not give any explanation.
Is this merely a fact, or something that can be logically rationalized ?
A ...
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Can nickel(IV) be stabilised in water using appropriate ligands?
Platinum(IV) is perfectly stable in water as its hexachlorido complex, and so is palladium(IV). However, nickel(IV) is not stable in water even in its hexafluorido complex- the exchange-inertness of ...
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Why do radical inhibitors inhibit a reaction by creating a "more stable" radical, but for monohalogenation, we WANT to form the most stable radical?
According to my notes, radical inhibitors tend to turn a more reactive radical into a less reactive radical by making it more stable. For instance, the hydroquinone reacts with a radical species, ...
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Do the phosphoester and glycosidic bonds of dNTPs increase thermal stability?
A while ago, I provided an answer to a question on Biology.SE concerning the half-life of dNTPs under PCR conditions. At the beginning of my answer, I give a qualification:
Caveat: ignoring the ...
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Hazards of eating non-stick coating, particularly considering the coating primer [closed]
How unhealthy are teflon / non-stick coating chips that end up eaten? What role does the primer coating play?
Existing similar threads that don't go into enough detail: 1, 2
I understand that there is ...
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Finding the order of decreasing rate of solvolysis of the following molecules with aqueous ethanol [closed]
In this question, I need to find the order of decreasing rate of solvolysis of the above molecules with aqueous ethanol.
I think this can be done by finding the species that can form the most stable ...
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Carbocation Stability question
Arrange, the following carbocation on increasing order of stability:
What have I though is that in second it will be most unstable, as $\ce{-OH}$ group will create most inductive effect (negative), ...
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Comparing stability of two carbocations [duplicate]
Which of the following ions(A and B respectively) is more stable? How can we explain this on the basis of resonance?
Here's what the solution said:
Structure (A) is a primary carbocation and has no ...
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