Jump to content

hypervalent_iodine

Administrators
  • Content Count

    4530
  • Joined

  • Days Won

    9

hypervalent_iodine last won the day on February 28

hypervalent_iodine had the most liked content!

Community Reputation

1324 Glorious Leader

About hypervalent_iodine

  • Rank
    Empress of Everything

Profile Information

  • Interests
    Organic and medicinal chemistry
  • College Major/Degree
    Ph.D. in medicinal / synthetic chemistry and mycology
  • Favorite Area of Science
    Organic Chemistry
  • Occupation
    Postdoctoral research fellow

Recent Profile Visitors

92463 profile views
  1. A lot of journal websites do this, as does (I think) PubMed. I’m not sure how good it is, but it exists.
  2. I think my approach with reviews and reading papers largely mirrors yours for the same reasons, although I tend to use SciFinder and Google Scholar rather than PubMed. Usually after the first pass through to filter out obviously irrelevant papers, I download all of the references + abstracts and then read enough of the papers to be able to categorise in EndNote before I move on to reading them more in depth as I write. I can also look up papers related to particular chemical structures or reactions using structure searches, which is very helpful in capturing as much of the literature as possible, although it doesn't always work depending on the topic. More broadly, I find that subscribing to certain journal email lists in your field is a good way of keeping an eye on what's happening in the field. I don't always scan every email I get, but I will usually look through the list of online preprints from journals like J. Med. Chem. or J. Org. Chem. and read the papers I think look interesting. Admittedly, unless I really want to know something specific about a protocol, I often skip the methods section.
  3. ! Moderator Note I'm not totally clear on what you're asking here, but please note that we have a thread related to potential COVID-19 antivirals and would ask that you post there.
  4. Hydrogen bonding requires a polar atom with a lone pair of electrons, such as nitrogen and oxygen, and an electropositive hydrogen in a polar bond, such as -OH hydrogens and -NH hydrogens. So, the ether can't actually H-bond to itself because it doesn't meet the second requirement, but the alcohol and carboxylic acids both can.
  5. Not quite. Three of these molecules can undergo hydrogen bonding. One cannot. Since they are close in terms of molecular size, you can rank them roughly by looking at the number of potential hydrogen bonds they can form to other molecules. Acetic acid has two oxygens that can both hydrogen bond, and a polar hydrogen that can form hydrogen bonds. Ethanol has one oxygen and a polar hydrogen, and diethyl ether only has an oxygen. Ethane has nothing that can hydrogen bond. Hence, you might predict that acetic acid would have the highest boiling point, since it has the highest number of potential hydrogen bond sites, followed by ethanol, diethyl ether, and then ethane.
  6. Firstly, what do you know about the solubility of sodium and other Group I metal compounds? Have you written out the balanced reactions? You don’t need to know what the initial iron compound is for this, just assume you have either Fe 2+ or Fe 3+ ions (as in, write two equations).
  7. On average, the OH bond will be polarised. In fact, it can participate in a particular type of dipole interaction called hydrogen bonding. As with all electrostatic interactions, it is not overly strong when you compare it to covalent bond strengths, but hydrogen bonds are considered quite a bit stronger than other intermolecular attractive forces. I have bolded a sentence that is not quite right. You won't covalently bond two ethane molecules together. You will get Van der Waals (also London dispersion forces) between molecules of ethane, but that's about it. They are very weak interactions. You will also get Van der Waals interactions with alcohol molecules. When you compare the two, you have (for example) ethanol, which has hydrogen bonding and Van der Waals interactions, and ethane, which only contains Van der Waals interactions. As you noted above, the stronger the interactions and the more of them that there are, the more energy it requires to break intermolecular bonds and pull molecules apart, which translates to a higher boiling point. As such, you would reasonably expect ethanol to have a higher boiling point to ethane. Another interesting comparison is between diethyl ether, acetic acid, ethanol and ethane. Can you predict the order of boiling points between those molecules from highest to lowest?
  8. Nitrogen can’t accommodate 5 covalent bonds. It can and does form ammonium salts, with the halogen acting as a counter ion.
  9. Lord, yes, you’re very right and that was a very stupid mistake on my part. Working from home has fried my brain. To your question, you need to consider that the molecules are all salts. Have you constructed molecular diagrams for the molecules to know how many bonds and lone pairs they have?
  10. Yes, more or less. So with an alcohol, can you identify what sort of intermolecular interactions might exist? Hydrogen bonding, London dispersion, dipole, Van der Waals, etc.?
  11. Formal charges of the atoms is not the same as the net charge of the molecule. For example, H2O has a net charge of zero, but the formal charges for the atoms are +1 (hydrogen) and -2 (oxygen).
  12. As of a few minutes ago, I went ahead and merged many of the threads and posts regarding Coronavirus into three threads: I understand that many have questions regarding coronavirus / COVID-19, but I think we can do without 20 different threads on the topic. To reduce clutter, I have created the above threads, and would ask members to please direct their questions / findings to the relevant one. If anyone objects or thinks I have missed something, please let me know. I myself am working from home; time is a luxury I have far too much of at the moment.
  13. ! Moderator Note I have merged a number of threads and posts into this one to decrease the clutter.
  14. ! Moderator Note Okay. I have moved a number of threads and posts into this thread and renamed it (from, "The sitting duck feeling"). We do not need a dozen threads asking similar or the same questions, so in an effort to reduce the clutter I have moved a number of threads and posts into this thread and renamed it (from, "The sitting duck feeling"). I am sorry if this has made the thread a little confusing, but I'm sure we can all manage. I have also merged several threads specifically addressing the topic of antivirals against COVID-19, found here.
  15. ! Moderator Note I have merged several threads into another to cut down on the number of threads on COVD-19 that are asking more or less the same questions. I haven't merged this one as it would have made that thread a little confusing, but if you wish to respond to anything posted here, please feel free to quote the relevant posts in the one I have kept open.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.