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This is a method to generate alternate Lewis structures of the same molecule. Here are two examples from the cumulative dissertation by Sascha Urbaczek[1]: If you were to search for the left molecule in panel (1) using an image search or a SMILES string, you might miss the right molecule in that panel. According to the RDkit document cited in the question, ...


6

It appears to be Δ⁹-tetrahydrocannabinol, also known as Δ⁹-THC: (Image source: 2D structure of tetrahydrocannabidiol (THC) by Harbin (Wikimedia)) The comment by The_Vinz about “pothead tattoo” was very … insightful.


5

For centro-symmetric space groups such as this one, the origin coincides with the center of inversion. You can see this specifically for this group if you look at symmetry operation (13): $$\overline{1} \mathrm{\ at\ } 0,0,0$$ Of course, there an an infinite number of origins in an infinite lattice because of the translational symmetry. In the tables, the ...


4

Mole itself doesn't have a magnitude, but the value of mole does, in fact it is the magnitude. Any measurement has a magnitude (ie for the mass of 5 kg the magnitude will also be 5). I think you are confusing it with scalar measurements (ie forces) which also have a direction. For example 5 Newtons 'in that direction'. Mole is similar to a dozen (just a ...


4

Technically liquid, but close to the boiling point and a bit nasty to work with, is carbon disulfide. It melts at about -112°C and boils at +46°C.


4

In the painting "Dream Caused by the Flight of a Bee" by Salvador Dali, among other strange items, we may see a fish flying in midair. There is also one in the drawing "Big Fish Eat Little Fish" by Bruegel the Elder. One may conclude that there is a flying fish in every picture out there. One may even publish a paper to that effect. But I believe you see the ...


4

I agree with the redditors that the answer is likely a polyoxometalate. $\ce{Na48[H_xMo368O1032(H2O)240(SO4)48] · \text{ca.}~1000 H2O}$ aka $\ce{\{Mo368\}}$ (core: $M \approx\pu{60.7 kDa},$ dimensions $\approx \pu{2.5 nm} × \pu{4.0 nm})$ is the primary candidate [1]: Figure 2. Structure of 1a in crystals of 1 in polyhedral (a) and ball and stick (b)...


4

CHFClBr, CHClBrI are examples. You can substitute hydrogen atoms with halogen atoms by radical halogenation reactions.


3

According to the rules, yes, Ammonia can be drawn with three of it's atoms in one plane and the other outside the plane. Here's an example, along with a 3D projection: However, what do you comprehend from this structure? This structure does not convey the trigonal pyramidal geometry of the molecule very convincingly. It might be mistaken for trigonal ...


3

I can think of two reasons that a 'maximum energy' might exist for a molecule: We can rigorously define the atomization energy for a molecule - that is, the enthalpy required to completely separate a given molecule into constituent atoms. As mentioned above, above a certain vibrational energy, the vibration will dissociate (e.g., one can break a C-H bond in ...


2

This is a tool to classify molecules with multiple rings. Here is an example from a PhD thesis: So even though you can find six-membered and eight-membered rings in this structure, these are made up of multiple four-membered rings, and are thus not parts of the set of rings. As the picture illustrates, it is sufficient to choose five rings to show the ...


2

I do not know VESTA well enough to provide an answer for this program. However because your data are about a crystal structure I suggest to export your model in the .cif format. CCDC's freely available version of CCDC's Mercury is able to read this file type, and add to its visualizations the symmetry elements of the unit cell (Display -> Symmetry Elements)...


1

Option $(3) N, N, N$ is correct. According to IUPAC, the definition of one mole is as follows: The mole, symbol $mol$, is the SI unit of amount of substance. One mole contains exactly $6.02214076 × 10^{23}$ elementary entities. This number is the fixed numerical value of the Avogadro constant, $N_A$, when expressed in $mol^{−1}$, and is called the ...


1

Solved. The problem was a typing error in the text book $ A_r $ for carbon should of course be 12 not 56. This is given correctly in the periodic table shown on the back cover but was misprinted in the body of chapter 1 of my book. Thanks to Zenix for pointing this out in comments. $ M_r $ of $ (CH_3CO)_2O $ Carbon C, $ A_r = 12 $ Hydrogen H, $ A_r = 1 ...


1

Inelastic collisions are such collisions, that dissipate mechanical energy to other energy forms. It may be e.g. acoustic energy, light, thermal energy ( in macro context only ) or internal energy of an object. The change of the internal energy in molecular context can be creation/breaking of chemical bonds, or changes of electron energy states. In usual ...


1

One mole of a compound does not have $\ 6.02· 10^{23}$ atoms, as you say. One mole of a compound has $\ 6.02· 10^{23}$ molecules One mole of water has $\ 6.02· 10^{23}$ molecules H2O, and $\ 3 · 6.02· 10^{23}$ atoms. One mole of H2O has $\ 6.02· 10^{23}$ atoms O, and $\ 2·6.02· 10^{23}$ atoms H.


1

Introducing the idea of "infinite atomicity" can be useful to highlight the importance of particle size on the properties of metallic or network covalent solids. As the surface to volume ratio of discrete particles becomes sufficiently large, properties of crystalline solids such as melting point, absorption wavelength and reactivity begin to diverge ...


1

I believe this website will be of use to you http://molview.org/ It appears to take names, formulas, smiles etc. If the name/formula/smile ID pops up in the search bar, it will draw it for you. Its database seems quite large, I use it for some pretty big drug molecules. It draws 2D and 3D images, and it also does single/double/triple bonds.


1

Rather than starting out with 100 g of unknown, I would start out with 1 mol of unknown, i.e. 283 g. That way, you can directly calculate how many moles of each element are in one mole of compound: $$ n = 67.3 \% \cdot \frac{\pu{283 g}}{\pu{12 g mol-1}} = \pu{15.86 mol}$$ Or to get the stoichiometric coefficient $\nu_C$ directly, take the percentage and ...


1

In Python you could try pysmiles. Starting from the SMILES description you should be able to create a NetworkX graph object with code along the lines of from pysmiles import read_smiles import networkx as nx smiles = 'C1CC[13CH2]CC1C1CCCCC1' mol = read_smiles(smiles)


1

To answer your question, what makes a compound a dehydrating agent is, in my opinion, stability, a good affinity for water and possibly inertness (or in special cases, selective activity but in reforming a designated salt, see example below). Now, $\ce{P2O5}$ is a white powder that loves water, in fact, it reacts violently and exothermically with water ...


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