Questions tagged [decomposition]
For questions about the decomposition of any chemical species, under any certain conditions.
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Under what conditions does manganese dioxide lose its catalytic property?
We know that under standard conditions (room temperature and 760 mmHg air pressure) we have this reaction:
$$\ce{2H2O2(l) ->[MnO2] 2H2O(l) + O2(g)}$$
Here, manganese dioxide is behaving as a ...
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Do mechanically recycled plastics decompose more rapidly?
Does it mean that mechanically recycled plastics decompose more rapidly in the environment? So even if mechanical recycling doesn't prevent plastics from going to landfills, just puts it off (...
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What is the chemical equation of the decomposition of natural cork? [closed]
I am currently doing a study project on natural cork wine stoppers and I am investigating the emissions of composting natural cork (C123H182O56N). However, I am struggling with setting up the chemical ...
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Does this coupled reaction actually happen (decomposition of calcium carbonate)
I found the following example of a coupled reaction to drive the decomposition of calcium carbonate. I get the calculation part of it, that the changes in Gibbs energy sum to a negative amount. But ...
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Is a diluted aqueous solution of sodium hypochlorite more stable than a concentrated solution, all else being equal?
On the Clorox website, they recommend that you dilute bleach (NaOCl) in water prior to use for disinfection. They say that you should make a fresh solution each time you need to use it, adding: “Don’t ...
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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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Rate of Decomposition of Sodium Thiosulphate
I want to calculate the activation energy of the decomposition of sodium thiosulphate, as a part of my school research project. I am aware that I must use the Arrhenius equation where the rate of ...
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Why is it that not all metals produce hydroxides when reacting with water? [duplicate]
I was taught, as a rule, that:
metals + water $\rightarrow$ metal hydroxide + hydrogen gas
$$\text{Na} + \text{H}_2\text{O} \rightarrow \text{NaOH} + \text{H}_2$$
However:
$$3\text{Fe} + 4\text{H}...
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How is this reaction not a decomposition reaction? And are all disproportionation reactions decomposition reactions?
When I asked my teacher whether all disproportionation reactions are decomposition reactions, he stated the following reaction:
$$ \ce{4 KClO3 -> 3 KClO4 + KCl} $$
and said that this isn't a ...
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What catalysts can be used to decompose nitrous oxide?
Constraints:
I'm going to need to use a lot of this stuff in various locations, so I'd prefer it not be expensive (leaving out things like platinum, palladium, and rhodium.)
While I don't believe I ...
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Do all metal nitrates give nitrogen dioxide on decomposition?
Some metal nitrates decompose to give nitrites: $\ce{2MNO3 -> 2MNO2 + O2}$
whereas some metal nitrates decompose to give $\ce{NO2}$. A possible reaction is $\ce{M(NO3)2 -> MO + NO2 + O2}$
Based ...
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Decomposition of Hydrogen Peroxide Catalysed by Potassium Iodide in Basic Solution
As part of my high school project, I had to measure the initial rate of decomposition of hydrogen peroxide catalysed by potassium iodide at different pHs. At higher pHs (alkaline conditions), I found ...
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Symbolic form of equilibrium constant for ammonium carbamate dissociation
$$\ce{NH2COONH4(s) <=> 2 NH3(g) + CO2(g)} \qquad K = \left(\frac{p(\ce{NH3})}{p^\circ}\right)^2\times\frac{p(\ce{CO2})}{p^\circ}$$
Assuming that you start this experiment with pure solid $\ce{...
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treating PLA (Polylactic acid) plastic to make it biodegradable
I am using PLA for 3D printing, and I know it does not degrade well in the wild. I would like to know if there is a chemical process I could use to treat it at home.
Specifically, I am looking for a ...
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Using the mass of calcium carbonate, what volume of carbon dioxide could theoretically be obtained if the reaction progressed to completion?
Using the mass of calcium carbonate $m(\ce{CaCO3}) = \pu{0.500 g}$, what volume of carbon dioxide $V(\ce{CO2})$ (in $\pu{mL})$ could theoretically be obtained if the reaction progressed to completion? ...
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How would one determine the temperature needed such that hydrogen peroxide will start to decompose? [closed]
Hydrogen peroxide decomposes at room temperature and so I was wondering what temperature is sufficient for this decomposition to occur.
Can someone explain how we can determine this? (theoretically or ...
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Strange Distillation Behavior
I was attempting a fractional distillation with 1mL water and 1mL propylene glycol, and I’ve been encountering strange behavior with the heating of the mixture. The heating curve shows strange “spikes”...
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How to neutralize the stink of decomposed fish?
Recently I discovered for myself an interesting way to easily produce home made plant fertilizer that is quite effective (tested myself on the plants). It's fish emulsion (so can be used also in a ...
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Software for modelling decomposition reactions
What are some good softwares that can model a decomposition reactions?
I have a reaction of H2O2 decomposing on metal exchange hexaaluminate catalyst. The catalyst is present in a packed bed thruster. ...
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What are the most potent hydrogen peroxide decomposition catalysts available to an amateur? [closed]
Some months ago I was playing with $60\,\%$ $\ce{H2O2}$ and unknowingly I used a silver spoon to transfer the liquid from a container, and the peroxide immediately started bubbling (it did look and ...
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How can I analytically calculate the rate of thermal decomposition of calcium carbonate?
I am a first-time poster on Chemistry StackExchange, and not much of a chemist.
I'm trying to determine the rate of thermal decomposition (in mol/s) of calcium carbonate ($\ce{CaCO3}$) at various ...
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Basic Chemistry: Carbon Dioxide Formation Unsure about Reaction [closed]
I have the following question description:
Consider a gas composed of $\ce{CO_2}$, $\ce{CO}$, $\ce{O_2}$ and $\ce{O}$ with 1 $\ce{C}$ nuclei for every 2 $\ce{O}$
nuclei.
I am trying to write ...
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Risks from overheated phenolphthalein in green/orange silica gel drying
Recently I tried to dry out some indicating silica gel. When I googled, I found advice on line saying that it should be heated to 150 C and that such was a standard procedure, so I popped it into the ...
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Half-life and shelf-life of second-order reaction
For integrated rate laws, I have attempted to find the shelf-life and half-life of second-order reaction:
However, the answers I have obtained (which are labelled with a red cross) are very different ...
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Can Aluminum Hydroxide (Al(OH)3) be heated to it's melting temperature before decomposing?
On the wikipedia page for aluminum hydroxide the listed melting point is 300 °C (572 °F), but in the same page it states that aluminum hydroxide decomposes at only 180 °C (356 °F). Can aluminum ...
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Diluting 4 % NaOCl to get a 1 % solution
Assuming that one has a 1 litre bottle of liquid bleach containing $4~\%$ sodium hypochlorite. If I wish to dilute it down to $1~\%$ sodium hypochlorite (to use as disinfectant), would adding 3 litres ...
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Long Term Storage of D-Cell Battery
I plan to store D-cell batteries in a winter home. The shelf-life is finite: is there any reason not to freeze or refridgerate the batteries to extend the shelf life?
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Algae Cultivation Using Polyethylene Film Reactor Vessel Floating In Pool with Algicidal ClO2 Concentration
I'm attempting to grow chlorella algae in a polyethylene film bag (which contains the growth medium) submerged in a temperature-moderating, above-ground swimming pool. This presents a challenge in ...
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How can we tell if a salt will melt or decompose?
Take $\rm NaCl$ for instance, a salt that will melt when it reaches its melting point, and compare it with $\rm NH_4NO_3$, a salt that doesn't melt, but instead decomposes to $\rm N_2O$ and $\rm H_2O$ ...
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What does HClO2 aqueous solution decompose to in an open environment? [closed]
I looked up the decompositions of diluted $\ce{HClO2}$ aqueous solution (used in a disinfectant) to know if it is safe to use on some substances, such as metal, wood, leather or skin. However, the ...
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What is the "mechanism" of the decomposition of hydrogen peroxide?
In my classwork on the decomposition reaction of hydrogen peroxide by catalase, I wrote the following equation:
$$\ce{2H2O2 -> 2H2O + O2}$$
However, my teacher said that I should go further in ...
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Thermal Decomposition of Sulfur Hexafluoride
What is the thermal decomposition temperature for $\ce{SF6}?$ I've heard it decomposes into $\ce{F2}$ and $\ce{SF4}$ only to decompose further into $\ce{S2}$ and $\ce{F2},$ but I haven't found much on ...
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Preparation of Barium Hexaaluminate using co-precipitation reaction mechanism
I am preparing Barium Hexaaluminate (BHA) using $\ce{Ba(NO3)2, Al(NO3)3}$, and $\ce{(NH4)2CO3}$. For $\pu{1 mol}$ of each $\ce{Ba(NO3)2}$ and $\ce{Al(NO3)4}$, I am using $\pu{1.5 mol}$ of $\ce{(NH4)...
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When MgCl₂ · nH₂O is heated to the boiling point of H₂O
When magnesium chloride hydrate is heated, does $\ce{Mg(OH)2}$ form or what? I'm curious, because Wikipedia says that it decomposes to release $\ce{HCl}$ gas.
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Why are ions much more efficient than electrons at beam-induced deposition?
I have recently been reading about electron beam induced deposition and ion beam deposition. The idea is to send a high energy (5-30 kV) beam of electrons/ions focused down to a spot on a material and ...
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Anhydrous Chromium Alum production
I recently started a small project of making home-made chromium alum crystals, as can be found on many sites, videos and recipes all around the internet.
I tried calculating the amount of salt I ...
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Thermal decomposition of steam to hydrogen and oxygen; at what temperature is half decomposed and how to calculate?
In comments below this answer in Space Exploration SE I've said:
(Wikipedia) says that dissociating water costs about 4.4 eV per bond. If 𝑘𝐵𝑇= 4.4 eV and $k_B$ is 8.617E-05 eV/K then that ...
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What does ethylene glycol decompose to when exposed to air for an extended period of time?
I came across this article on wikipedia on ethylene glycol stating that it decomposes fairly quickly. I was under the impression that ethylene glycol was dangerous to let leach into soil, but I think ...
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Decomposition of Metal Nitrates
An entrance JEE Main & Advanced AIEEE 2003 exam question:
Which one of the following nitrates will leave behind a metal on strong heating?
A. Copper nitrate
B. Manganese nitrate
C. Silver nitrate
...
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Thermal decomposition of K2CO3
$\ce{K2CO3}$ doesn't boil. It thermally decomposes at $\pu{1200 ^\circ C}$. However, I find conflicting information online about this. Roughly what I have found say three inconsistent things:
It ...
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How to predict the decomposition products of for example barium carbonate?
I am a high school student studying basic chemistry and I am confused about the process of writing decomposition reactions.
The question I have encountered asks me to decompose $\ce{BaCO3}$.
Online, ...
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Could Calcium Oxide be made from CaCO3 in a bonfire?
I have some chalk and I need to turn it into CaO. Would a big bonfire be hot enough to make it? If anyone has personal experience with this reaction please share, whether succesful or not
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$K_c$ vs $K$ in equilibrium reactions
I don’t understand why the following question
The decomposition of nitrosyl bromide $(\ce{NOBr})$ proceeds by the following reaction:
$$\ce{2 NOBr(g) <=> 2 NO(g) + Br2(g)} \qquad K = 0.0142$$
...
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What is the most convenient way to prepare ferrous oxide (FeO) in the laboratory?
The Wikipedia page for ferrous oxide states that $\ce{FeO}$ can be prepared by the thermal decomposition of iron(II) oxalate, with the following reaction:
$$\ce{FeC2O4 → FeO + CO2 + CO}$$
And that ...
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What is the fate of sulfur in cysteine when it participates in gluconeogenesis?
Amino acids can be broken down to yield pyruvate, which in turn can be used to construct glucose molecule in the process of gluconeogenesis. What happens to the sulfur atom in the amino acid cysteine ...
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Why does Comfrey Break Down Easily? [closed]
comfrey (Symphytum officinale) is a well known plant to organic growers. One of its features is that the leaves break down very quickly, either in water or in a container closed from UV light. There ...
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Iron(III) nitrate and hydrogen peroxide reaction
When iron(III) nitrate is added to hydrogen peroxide as a catalyst, the temperature initially decreases and begins to increase after 30 seconds. Why is this the case? (is there any intermediate ...
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Methods and observations that help you achieve complete decomposition of a compound in decomposition analysis [closed]
Different chemicals decompose in different ways to give different observations, but they usually involve heating the compound to high temperatures.
My question is that what are your lab techniques ...
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Does ethanol "decompose" or "remove" phosgene from chloroform?
A question I was asked was: "Why is ethanol added to chloroform bottles?". I know that chloroform can be slowly converted to poisonous phosgene gas, and that ethanol is added to prevent phosgene ...
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Hydrogen peroxide and glycerol combination
Is the mixing of store-grade hydrogen peroxide 3% and glycerol in the ratio of 1:2 (V/V) at room temperature affecting the decomposition rate of hydrogen peroxide?
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