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18

Here is the Walsh diagram depicting all the valence molecular orbitals (a diagram showing how individual molecular orbitals change in energy due to bending around the central atom). Oxygen has 6 valence electrons, so ozone has 18 electrons in total. If we start on the right where ozone would be linear, we can see that all the orbitals up to the $2\pi_\mathrm ...


17

Since the stratosphere is nowhere near a closed system, a chlorine atom will eventually leave it. Look at the phrasing again: It is estimated that one chlorine atom can destroy over 100,000 ozone molecules before it is removed from the stratosphere. It is not stated, that it looses its potential, it just leaves the region, where there is sufficient ozone ...


11

Those are all valid resonance structures for ozone (except the second from the left in the "four-form structure" row, that one has two negative charges, maybe it's a typo). In fact you can draw even more structures like this one, where this is no single bond between the middle and terminal-right oxygens. All of these structures contribute to the "real" ...


10

Even if the UV light idea doesn't work out very well I still want a way to do this With some photochemical background, I suggest to forget about running such a UV lamp Remember that your plasma will be formed in air. For every molecule of ozone formed, there are much more harm- and odourless $\ce{O2}$ molecules around. If you cleave $\ce{O3}$ \[\ce{O3 + ...


10

You make the assumption that the ozone concentration in the upper atmosphere is in equilibrium. It isn't. $\ce{O3}$ is a much less stable molecule than $\ce{O2}$ (the heat of formation from $\ce{3/2 O2}$ is $143~\mathrm{kJ/mol}$) and the concentration at equilibrium would be very low. A significant concentration exists in the upper atmosphere because $\ce{...


9

This is a semi-standard example of why 'naive' balancing does not work. Ozone is a source of atomic oxygen, producing free oxygen molecules. So, in 'mild' conditions only one oxygen per ozone molecule would react as a strong oxidizer, and the remaining molecular oxygen would require elevated temperatures to react. Thus the equation would be $\ce{PbS + 4O3 -...


8

We are basically talking about a derivation of the $\ce{H2/O2}$ system, which involves a radical mechanism. You maybe want to have a look at this answer of mine going a bit more into detail. The reaction you are interested about is only a total sum of reactions and is most likely not to occur as other reactions will be favourable. Ozone itself is not a very ...


8

Shortwave UV light (100-240nm) has enough energy to knock an electron out of an $\ce{O_2}$ bond creating an excited molecule $\ce{O^{excited}_2}$ which decomposes to two free radicals of oxygen. Each of the free radicals then combines with different oxygen molecules to create a net of two ozone molecules. The crux here is that the electron is not "knocked ...


7

I would say it would be much easier to try to keep the area oxygen free. Atomic oxygen (i.e. $\ce{O}$) is a highly reactive radical. This would react either with another $\ce{O}$, or an $\ce{O_2}$. It is hard to avoid this unless you can get rid of the $\ce{O_2}$. Not sure what kind of a geometry you are thinking of, but purging the volume with $\ce{N_2}$ ...


7

Ozonolysis of the given compound gives $\ce{I}$ , $\ce{II}$ , $\ce{III}$ and $\ce{IV}$. $\ce{I}$ and $\ce{II}$ are Homomers and have same configuration "S" and therefore identical (as shown in the figure). $\ce{III}$ and $\ce{IV}$ are achiral . Therefore , the total number of optically active compounds formed after ozonolysis is $\ce{= 1}$.


6

The real answer for why ozone smells the way it does has little to do with chemistry but perhaps a lot to do with evolution. The specific reason why it is coloured far more intensely than oxygen is explained well in the previous answer but it is worth adding a simple point. There is very little reason to think that small changes in structure make only small ...


6

Our perception of colour and smell involve different chemistry so there is no reason why they should be related. For example, what ever the chemistry of smell is (and its not certain what this is) it clearly does not involving photons and subsequent isomerisation of a rhodopsin. Ozone is slightly coloured as it has two low lying electronically excited ...


6

This is because the electrons dont actually jump between the atoms of the molecule, but rather the electron cloud density is even distributed through the resonating bonds. If atoms had to hold formal charges this would be very unstable for the electron count. In essence all of the resonant structures exist at the same time. This lack of formal bonding in ...


6

What is the mechanism for the ozonolysis of a nitronate anion? Probably very analogous to ozonolysis of a double bond. A typical synthetic procedure is detailed in OrgSyn. Note the addition of dimethylsulfide during work-up; this is common in ozonolysis reactions as it helps reduce the ozonide and also reduces any other dangerous, highly oxidized by-...


6

I'm going to attempt to answer this from three points of view. Qualitative considerations and MO theory: First, why isn't ozone linear? You can imagine $\ce{O3}$ like a $\ce{CO2}$ molecule that lacks two electrons. This lack of electrons will result in less $s$-character, and less bonding "attitude". That's why ozone is bent. Still, the repulsion in its ...


6

According to Wikipedia, Martin is correct; a chlorine molecule, being slightly heavier than oxygen, will eventually be transported out of the ozone layer back to the troposphere (taking approximately 2 years to do so). Additionally, presence of other atoms in the ozone layer have a small chance of destroying the radical chlorine, causing it to form $\ce{HCl}$...


6

The given answer is correct. The product scheme you drew is correct as well. However, as I marked in your scheme (see below), products A and B are essentially the same enanthiomer (both have (2S)-configuration). The compounds you have drown in right-hand side are also an identical compound, which is not optically active. Therefore, ozonolysis has given only ...


5

Your guess about electronic repulsion is right: the repulsion between the lone pairs of electrons on the Oxygen atoms leads to intense repulsion at such close ranges leading to instability. In comparison to this resonance is a far far more stable configuration. Strain at the joints in the cyclic structure does its part as well because experimentally it is ...


5

This is basically an excerpt of the answer I have given to another quite similar question. Ben is quite right, neither the reaction nor the mechanism is simple. It involves several different radical chains all resulting in the decomposition of ozone.[a] It is most likely that the reaction will start with the formation of oxygen radicals in the gas phase ($\...


5

Ozone is a powerful oxidizer (redox potential of 2.07) and will kill bacteria and destroy viruses (not sure if I can say it kills viruses) by transferring oxygen atoms to them. It also decomposes in water forming OH radicals, which quickly oxidize organic and inorganic compounds. Ozone can also react by ozonolysis, breaking compounds which have double or ...


5

The product of ozonolysis depends on how you work up the intermediate ozonide. You are clearly familiar with the reductive workup (with dimethyl sulfide or PPh3) that gives two carbonyl compounds, aldehyde or ketone. But if you work up under oxidative conditions, as is the case here, you get carboxylic acids from mono-substituted double bonds and ketones ...


4

The catalytic stratospheric ozone destruction by CFC's and other compounds is almost certainly too complex to fully replicate in a laboratory with current technology. The only laboratory of proper scale and conditions is the earth's atmosphere as a whole (no pun here, seriously ;). Even the 1995 Nobel prize winners Crutzen, Rowland and Molina had made ...


4

If you look at the molecular structure of ozone below, you can see that it is polar. Diatomic oxygen is non-polar. This mild polarity of ozone greatly enhances the solubility of the molecule in a polar solvent like water.


4

It would be more correct to describe ozone as an allotrope of oxygen. Dioxygen (about 1 in five of the molecules making up air) is another allotrope. The periodic table describes the atoms that make up elements as this is the most fundamental property. Many other elements, though, exist in multiple allotropes. Carbon, for example, has several: graphite, ...


4

If you look carefully, the reagent for the first step is $\ce{O3/H2O}$, which is used for Oxidative ozonolysis. If the mechanism of ozonolysis is drawn, you will realise that a molecule of Hydrogen peroxide($\ce{H2O2}$) is released by the oxidation of the alkene to aldehyde and if that $\ce{H2O2}$ is not removed from the reaction mixture, it will oxidize the ...


3

Smell: this is going to be lie. Simple answer: ozone is way more reactive (more poisonous than Cl2 that was used in WWI), so it burns your nose, nakes reactive chemicals that you smell. Correct answer. Brain receives the map of smells. There are no receptors (in the usual understanding) in the nose. That is why people change smell perception as they age. ...


3

Final conditions ($\pu{1.0 atm}$) give a hint at what altitude the thickness should be estimated – at the Earth's surface. Let's denote the unknown thickness as $h_x$, radius of the Earth as $r_\mathrm{E} = \pu{6371 km}$; also take $h_1 = \pu{15 km}$ and $h_2 = \pu{35 km}$ and put these dimensions on a rough 2D sketch: Fig. 1. Schematic representation of ...


3

It's important to bear in mind stability is always a relative judgment. Things are stable or not only with respect to that into which they could turn. So we only say ozone is "unstable" because it can and will easily decompose into oxygen (O2) if given a chance. In some sense it might even be more correct to say what's important here is the stability of O2 ...


3

Ozonolysis is a synthetic procedure deploying diluted ozone as a reagent. This reaction may be relevant in the context of your question, because i) during the reaction, the gas typically is bubbled across a solution (and you have some exhaust to deal with), and ii) even more importantly, after the reaction, the organic products are to be isolated safely, ...


3

The ozone molecule is described with two resonant structures(as in figure) in which all the oxygen atoms respect the octet rule. The oxygen in the middle has a positive charge because has only 5 valence electron and the oxygen with the single bond has a negative charge because it has 7 valence electrons. In the real molecule both the bonds have the same ...


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