All show needs three hundred pounds, where you will share three pairs of electrons to make three single bonds. Now, if we have an age to an age to which will have to bonds in here, we would now have a complete optic. And if we have an H for we have a next Tre electron in the in the nitrogen octet, so it would not make it stable. Um, it would not make stable molecules. That's why an ace tree is the most favored species. Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties.
Chemistry deals with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds. Chemistry also involves understanding the properties and interactions of individual atoms and molecules for use in larger-scale applications. In chemistry and physics, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic particles, and in everyday as well as scientific usage, "matter" generally includes atoms and anything made up of them, and any particles and objects that act as if they have both rest mass and volume.
However it does not include massless particles such as photons, or other energy phenomena or waves such as light or sound. Matter exists in various states known as phases that are defined by various physical properties, such as state of matter, phase, shape, and density. The Standard Model of particle physics and the general theory of relativity describe fundamental particles and the fundamental forces acting between them that control the structure and dynamics of matter.
Click 'Join' if it's correct. Emily M. Chemistry 6 months ago. View Full Video Already have an account? Jessica L. Answer Use covalent Lewis structures to explain why the compound that forms between nitrogen and hydrogen has the formula NH3. Discussion You must be signed in to discuss. If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given.
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Issue 27, From the journal: Physical Chemistry Chemical Physics. Wish I had found this website months ago. All the information is so accessible and very well organized. Keep up the tremendous work. There is a mistake in the second paragraph, I think. An atom can never be neutral and charged at the same time. I recommend you to say an atom becomes an ion negatively charged to reach the full octect.
You made very simple. Are there other factors beside PKa? So, if the base is weak, it will not be in a hurry to accept protons and react.
Hence, as the base is not readily reacting, it is stable and a good leaving group. Weak bases are very stable as anions in solution on their own.
A weak base has a strong conjugate acid e. HCl is the strong conjugate acid of the weak base Cl-. Since the acid is strong, we know that the base must very readily leave. Moderately strong bases, like NH3 are poor leaving groups, and strong bases like OH- are terrible leaving groups.
By far the most coherent explanation of nucleophiles and leaving groups I have seen so far. Better than Youtube and most text books for that matter! What if there are two identical leaving groups on different parts of the molecule? Say, two bromines. What factors do you look at when choosing the leaving group then?
Then you would examine the carbon that the leaving groups are attached to. Primary, secondary, or tertiary? Then you would look at the reaction conditions i. I ve seen alkoxides getting removed during sn2th reactions related to carbonyls. Minor fix needed on the first image: the reactants side is neutral while the products side is positive need to either add a negative formal charge to Nu or take off the negative formal charge from L.
Could u explain why F can become a leaving group when it is attached to a carbonyl carbon or an aromatic ring? Yes, F- is an OK leaving group in those situations nucleophilic aromatic substitution because the rate limiting step is attack of the aromatic ring disrupting aromaticity. Loss of the leaving group is slow compared to that step.
Also, because F- is so electron withdrawing, F actually helps to accelerate the reaction by removing electron density from the ring and making it easier to attack. James, someone mentioned the difference for F- between protic and aprotic solvents, do you mind shedding some light and clarity on this, please?
This effect is biggest for fluorides because they are so small and not easily polarisable. No matter the solvent, F will be a poor leaving group in nucleophilic substitution and elimination reactions.
I- is a BLG than F- in aprotic solvents. F- is a BLG than I- in protic solvents. If something is a poor nucleophile it has to be BLG.
I am right , right? Ex:F- in protic is much more stable than I- due h bond. This is absolutely amazing. I will never be able to thank you enough or express how much this has helped me.
Seriously, you are a god in my eyes right now.
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