Subscriptions are available and billed automatically at the rate depending on the selected subscription plan. Unleash the power of Nova ChatGPT now and enjoy unlimited access to all the app's features. In case of any questions or inquiries, you can reach us at. The information provided by Nova AI is for informational purposes only and should not be considered official or authoritative. Please note that Nova ChatGPT is powered by OpenAI's ChatGPT API but is an independent app not associated with OpenAI, any government, or political entity. Remember to download the Nova app now and unlock the potential of your AI-powered virtual assistant. Benefit from unlimited questions and answers, multi-language support (140+ languages), and a chatbot that remembers your full chat history. Available on Android phones, Wear OS, tablets, and web, Nova AI is the #1 cross-compatible platform for accessing the latest AI technology from OpenAI in the most user-friendly way. Download Nova - Your AI Assistant NowĮxperience the extraordinary benefits of Nova ChatGPT Chatbot app today. Download the Nova app now and have your AI-powered virtual assistant always at hand. Its versatility extends beyond conversation as it can also recommend books or movies, adding a touch of personalized assistance to your interactions. This AI-powered companion is capable of producing human-like responses, creating a conversational experience that mimics talking to a close friend. Whether you're seeking amusement, advice, or simply in need of someone to talk to, Nova ChatGPT is always available for you. Reliable Chat Partner for Any Conversation Express yourself confidently and flawlessly with Nova AI's proofreading capabilities. Whether you're writing an important report, an academic paper, or even a simple email, Nova's AI proofreader ensures your grammar, punctuation, and spelling are correct. It meticulously analyzes your written work and offers suggestions to help you create professional-grade documents. Nova ChatGPT is equipped with a top-of-the-line AI-powered proofreader backed by leading AI technologies. Its AI copywriter feature is perfect for creating ads, descriptions, sales pitches, and video scripts, while the AI content writer tool is ideal for content marketing purposes, such as blog posts, articles, and social media content. Nova AI can provide suggestions, generate creative ideas, and help you craft unique and engaging content. Whether you need assistance with emails, social media posts, or poems, this app is here for you. With Nova ChatGPT, you gain access to a versatile AI writing assistant that can help with various writing projects. Unlimited Assistance with Nova's AI Writing Assistant With Nova AI, you'll always have a reliable and friendly chat partner by your side. This innovative chatbot goes beyond simply answering questions and can even recommend books or movies to enhance your experience. It utilizes state-of-the-art language models to understand your questions and generate human-like responses, providing you with a chat experience that feels like conversing with a knowledgeable friend. Nova ChatGPT Chatbot app is a revolutionary chatbot powered by advanced AI technology.
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Huxley devised a story in which Lewis Carroll and Alice Liddell (the inspiration for Alice) were misunderstood and persecuted following the book's publication. In the fall of 1945, shortly after the war ended, Disney revived Alice in Wonderland and hired British author Aldous Huxley to rewrite the script. Realizing the amount of work needed for Alice in Wonderland, and with the economic devastation of World War II and the production demands of Pinocchio, Fantasia, and Bambi, Disney shelved production on Alice in Wonderland shortly after the screening. A story reel was completed in 1939, but Disney was not pleased he felt that Hall's drawings resembled Tenniel's drawings too closely, making them too difficult to animate and that the overall tone of Perkins' script was too grotesque and dark. Hall to develop the story and concept art for the film. He then hired storyboard artist Al Perkins and art director David S. In 1938, after the enormous success of Snow White, Disney bought the film rights of Alice in Wonderland with Sir John Tenniel's illustrations and officially registered the title with the Motion Picture Association of America. a cartoon where Mickey Mouse goes through a mirror and into a world where all the items in the house are alive. Nevertheless, Disney did not completely abandon the idea of adapting Alice, and in 1936 he made the Mickey Mouse cartoon Thru the Mirror. However, these plans were eventually scrapped in favor of Snow White and the Seven Dwarfs, mainly because Disney was put off by Paramount's 1933 live-action adaptation Alice in Wonderland. In 1933, Disney considered making a feature-length animated-and-live-action version of Alice starring Mary Pickford. The series began in 1924 before being retired in 1927. Disney and re-hired Kansas City co-workers including Ub Iwerks, Rudolph Ising, Friz Freleng, Carman Maxwell, and Hugh Harman to form the Disney Brothers Studios, which was later re-branded Walt Disney Productions. Winkler of Winkler Pictures agreed to distribute the Alice Comedies, and Disney partnered with his older brother Roy O. However, Disney left for Hollywood and used the film to show to potential distributors. Faced with business problems, however, the Laugh-O-Gram Studio went bankrupt in July 1923, and the film was never released to the general public. The short featured a live-action girl (Virginia Davis) interacting with an animated world. The last of Newman Laugh-O-Grams was called Alice's Wonderland, which was loosely inspired by the Alice books. In 1923, he was a 21-year-old aspiring filmmaker working at the Laugh-O-Gram Studio in Kansas City, making the unsuccessful short cartoon series by the name of Newman Laugh-O-Grams. Walt Disney was familiar with Lewis Carroll's Alice books and had read them as a schoolboy. The movie was based on Alice's Adventures in Wonderland and Through the Looking-Glass by Lewis Carroll. It follows a young girl named Alice who falls down a rabbit hole to enter a nonsensical world Wonderland that is ruled by the Queen of Hearts, while encountering strange creatures, including the Mad Hatter and the Cheshire Cat. Alice in Wonderland is an animation movie produced by Walt Disney Productions and directed by Clyde Geronimi, Wilfred Jackson, and Hamilton Luske in 1951. Purulent or pus-like discharge from your dog’s vulva is a major concern. You should call your veterinarian right away, as your dog may have a uterine infection called a pyometra. White or yellow pus-like vaginal discharge.If you see bloody discharge from your pregnant dog’s vulva, call your veterinarian right away hemorrhage during pregnancy or immediately prior to whelping is a sign of pregnancy loss. If seen, you should call your veterinarian immediately. Black discharge coming from your pregnant dog should cause serious concern. Vaginal discharge with an odor: Any vaginal discharge that has an odor is reason for concern, and a veterinarian should be called right away. The odor is indicative of either an infection or a dead pup.How to tell if a pregnant dog’s discharge is a reason for concernīelow is a description of the types of vaginal discharges that you should not ignore & may warrant a call to your vet as soon as possible: The plug is expelled hours to days before whelping. Your pregnant dog will most likely lick up the mucus plug before you have a chance to see it. The mucus plug covering the cervix will be expelled. It looks like a clump of stringy mucus similar to raw egg whites. Week 9ĭuring the ninth week, your dog will display more nesting behavior. She will have a decreased appetite and may be nauseous. She will have a decreased appetite and will start nesting behavior. Her mammary glands will become even larger. You should set up a whelping box at this time, as she is soon to deliver. The mucus-like discharge previously seen may continue. In the eighth week, your dog’s abdomen will be distended. Milk may be seen coming from the nipples, and the mammary glands will start to swell. A clear or white or yellow-tinged mucus-like discharge may be seen. In the seventh week, the abdomen will become more distended, a lot of weight will be gained, and the hair on the belly around the nipples will start to shed. Your girl’s appetite may decrease, taking her daily intake back to her pre-pregnancy normal. Your pregnant dog will continue to gain weight. You may see small to moderate amounts of clear to white, yellow, or pink-tinged mucus-like discharge. Your dog’s abdomen will increase in size and may become rigid as she starts to gain weight. Her nipples will get even bigger, and the veins on her belly will become dark and readily visible. Jamie Whittenburg Veterinarian Director at We have described below normal vaginal discharges that are seen during the nine weeks of pregnancy: First 3 weeksĭr. Normal vaginal discharges often seen in pregnant dogsĪ few factors come into play when trying to determine if a vaginal discharge is a problem, starting with the discharge’s color, odor, and when it happens (during the 9 weeks of pregnancy). Throughout this article, look out for special tips from our veterinarians Dr. We will then explain how to recognize when your dog’s vulvar or vaginal discharge requires veterinary attention. In this article, we will first describe normal vaginal discharges that you may see during pregnancy (week by week). You may notice some discharge coming from the vulva of your dog, which can be either normal or a sign of something wrong. We hope that everything goes smoothly during the nine-week gestation period. This article was updated on October 31st, 2023Ĭongratulations! Your dog is going to be a mother, which is very exciting news. As a result, it is unlikely that Amos 'n' Andy will ever be seen again on television. The very stereotypes that had so long been unfairly applied to an entire race were used throughout. AMOS AND ANDY SHOW COMEDY OLD TIME RADIO SHOWS ALL NIGHToldtimeradio otr comedySUPPORT THE CHANNEL BY JOINNG. Nevertheless the humor certainly derived from the fact that these were shiftless, conniving, not-too-bright blacks. Actually the series had many episodes that showed the Negro with professions and businesses like attorneys, store owners, and so on, which they never had in TV or movies before." Others pointed out that the situations were no different than those found in many comedy programs with white characters. The creators certainly didn't think so, and actor Alvin Childress (Amos) was quoted as saying, "I didn't feel it harmed the Negro at all. CBS found its market for the films suddenly disappearing, and in 1966, the program was withdrawn from sale, as quietly as possible.Īs to whether the program was in fact racist, there was no agreement on that. This focused attention a new on the old controversy and in the summer of 1964, when a Chicago station announced that it was resuming reruns, there were widespread and bitter protests. Soon afterward, an official of the Kenya government announced that the program would be banned in his country. The turning point came in 1963 when CBS Films, which was still calling Amos 'n' Andy one of its most widely circulated shows, announced that the program had been sold to two African countries, Kenya and Western Nigeria. Amos 'n' Andy drew sizable audiences during its two-year CBS run, and was widely rerun on local stations for the next decade. Madame Queen was Andy's friend and Lightnin' was the slow-moving janitor at the lodge.Ĭivil rights groups such as the NAACP had long protested the series as fostering racial stereotypes, to little avail. remember, we is brothers in that great fraternity, the Mystic Knights of the Sea."Īmos was actually a rather minor character, the philosophical cabdriver who narrated most of the episodes. More often than not, Kingfish would get them both into trouble, but win Andy's cooperation with an appeal to fraternal spirit-"Holy mackerel, Andy! We's all got to stick together in dis heah thing. The Kingfish was constantly trying to swindle him in one way or another, but the "big dummy" (as Kingfish called him) kept coming back for more. Andy Brown was the most gullible of the lodge members, a husky, well-meaning, but rather simple soul. Mama, in particular, didn't trust him at all. That put him at odds not only with them, but with his wife, Sapphire, and her mother. As head of the Mystic Knights of the Sea Lodge, where he held the position of "Kingfish," he got most of the lodge brothers involved in his schemes. Set in Harlem, Amos 'n' Andy centered around the activities of George Stevens, a conniving character who was always looking for a way to make a fast buck. Only Ernestine Wade and Amanda Randolph were brought over from the radio cast. Since they were white, and the entire cast of the show on television had to be black, a much ballyhooed search was held, over a period of four years, to find the right actors to play the parts. The series was produced by Freemad Gosden and Charles Correll, the two actors who had created and starred in the radio version. Wyatt produces 21 hours a week of freshly minted Classic Radio Theater presentations each week, and each day’s broadcast is timely and entertaining!Amos 'n' Andy - 131 Mp3 Downloads Available "Amos 'n' Andy", is one of the most popular and long-running radio programs of all time, was brought to television in the summer of 1951. It’s a true slice of life from not just radio’s past, but America’s past. FDR, Eisenhower, JFK, Reagan, Carter, Nixon, LBJ. But more than just “playing the hits”, Wyatt supplements the first hour of each day’s show with historical information on the day and date in history including audio that takes you back to World War II, Korea, and Vietnam. Host Wyatt Cox brings the best of radio classics back to life with both the passion of a long-time (as in more than half a century) fan and the heart of a forty-year newsman. Heard on almost 100 radio stations from coast to coast.Ĭlassic Radio Theater features great radio programs that warmed the hearts of millions for the better part of the 20th century. If you enjoy our shows, listen via the links on our web page or if you're so inclined, Buy me a coffee! Also Claudia, originally broadcast October 29, 1948, Nourishing Cream before bed. The Kingfishs’s Mother in Law has fallen for a police officer. Amos n Andy, originally broadcast October 29, 1952, Momma’s Big Romance. I am unfortunately not able to bring a solution, just a synthesis of the issues, hoping it will Apple to take that long lasting issue into consideration. But where ?Īt last, my iPhone X (September 2017), uses Bluetooth version 5.0 and works perfectly well with the HK Onyx 5 studio: pairing immediately, sound control is perfect.
In source form as either a tar.bz2 package or a.Procedure that most users should follow after meeting the requirements listed MacPorts version 2.8.1 is available in various formats for download and installation (note, if you are upgrading to a new major release of macOS, see the migration info page): Install MacPorts for your version of the Mac operating system:.Install Apple's Command Line Developer Tools: xcode-select -install.Sudo /Applications/Install\ OS\ X\ Mavericks.app/Contents/Resources/createinstallmedia -volume /Volumes/MyVolume -applicationpath /Applications/Install\ OS\ X\ Mavericks. Sudo /Applications/Install\ OS\ X\ Yosemite.app/Contents/Resources/createinstallmedia -volume /Volumes/MyVolume -applicationpath /Applications/Install\ OS\ X\ Yosemite.app Sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia -volume /Volumes/MyVolume -applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app Sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia -volume /Volumes/MyVolume The following examples assume that the OS X installer is in your Applications folder and the name of your USB flash drive or other volume is MyVolume:.Replace volumepath with the path to your USB flash drive or other volume, and replace installerpath with the path to the Install OS X app.Ĭreateinstallmedia -volume volumepath -applicationpath installerpath Applications/Install\ OS\ X\ Yosemite.app/Contents/Resources/createinstallmediaĪpplications/Install\ OS\ X\ Mavericks.app/Contents/Resources/createinstallmedia Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia For detailed usage instructions, make sure that the appropriate Install OS X app is in your Applications folder, then enter one of the following paths in Terminal: Examples of this command are in the next section. Use the createinstallmedia command in Terminal to create the bootable installer. Open the Terminal app, which is in the Utilities folder of your Applications folder. You could also use a secondary internal partition. Mount your USB flash drive or other volume. The installer will be in your Applications folder. Quit the installer if it opens automatically after downloading. Use the 'createinstallmedia' command in Terminalĭownload the OS X installer from the Mac App Store. These advanced steps are intended primarly for system administrators and others who are familiar with the command line. With OS X El Capitan, Yosemite, or Mavericks, you can use a USB flash drive or other removable media as a startup disk from which to install OS X. Sudo /Applications/Install\ OS\ X\ Mavericks.app/Contents/Resources/createinstallmedia -volume /Volumes/Untitled -applicationpath /Applications/Install\ OS\ X\ Mavericks.app -nointeraction Make sure the downloaded installer package is installed in the Applications folder. Sudo /Applications/Install\ OS\ X\ Yosemite.app/Contents/Resources/createinstallmedia -volume /Volumes/Untitled -applicationpath /Applications/Install\ OS\ X\ Yosemite.app -nointeraction Prepare an 8GB USB drive labeled Untitled: Quit Terminal and continue the install.In the installer, choose Utilities > Terminal. To change the date from Terminal (which is likely all that will be accessible), follow these steps, which sets it to February 1st 2016 for example:.And set the clock in terminal prior to that date:.Pkgutil -check-signature /path/to/installer/app If you have installers for 10.9 Mavericks, 10.8 Mountain Lion, and 10.7 Lion check their certificates:.Apple Code Signing Certification AuthorityĥB DA B1 28 8F C1 68 92 FE F5 0C 65 8D B5 4F 1E 2E 19 CF 8F 71 CCī0 B1 73 0E CB C7 FF 45 05 14 2C 49 F1 29 5E 6E DA 6B CA ED 7E 2C Status: signed by a certificate trusted by macOSĢA A4 B9 97 3B 7B A0 7A DD 44 7E E4 DA 8B 53 37 C3 EE 2C 3A 99 19Ģ. Pkgutil -check-signature /Applications/Install\ macOS\ Catalina.app Softwareupdate -fetch-full-installer -full-installer-version 10.13.6 Downloading Full MacOS High Sierra 10.13.6 Installer Application in Catalina:.
Luckily, I worked out that I’d have a small window of time to run home and pull an outfit swap before my evening activities. The problem: How to look festive and stylish while still paying attention to the inclement weather that’s been pummeling the city? Enter metallic jeans! On a particular busy day during NYFW, I slipped on my slightly slouchy, waxy gold jeans and felt just the right amount of appropriate.īut as I glanced at my calendar, I realized that while I’d start my day show hopping at Lincoln Center, I would end it with a party hosted by Vince at the Top of the Standard Hotel in Manhattan’s Meatpacking District. When it comes to footwear and purses, it is recommended that they be cleaned with a gentle cloth after each use.Although it may be cold and snowy, that didn’t stop me from attending a number of shows and parties during New York Fashion Week.When you wear a lame material, you need to be very cautious since even a little snag might ruin your lovely lame clothing. Lame is prone to snagging and fraying because of its loose weave.When ironing fabric, use a pressing cloth in between the iron and the fabric. If you need to get rid of creases, put your iron on the lowest setting and press the clothing while it is facing the opposite way around.Be sure to keep your lame clothing away from sources of direct heat or sunshine. A clothes dryer is essentially the same thing. Because the heat might cause the metallic strands in lame cloth to melt, ironing the fabric is not suggested.The fabric is not washable by hand or machine it should only be cleaned by a dry cleaner.Similarly, silver or platinum lamé is coated with the same kind of finish. Gold lamé materials were susceptible to tarnishing until the mid-20th century, although this is no longer a problem.Still, it is common to use a gold-and-silver alloy to make the lamé thread last longer.Gold lamé thread used in modern fabrics is coated with clear plastic to make it stronger and keep it from tarnishing. A silver-to-gold alloy will eventually lose its shine, diminishing the appeal of true gold lamé clothes over time. The gold used in lamé manufacture was often alloyed with silver to increase the metal's tensile strength and durability.
So if you need additional storage for your brand-new iPhone, here are the best USB 3.0 flash drives you can buy. However, you can also use these USB 3 flash drives with any Type-C port which means they also work well with the USB 2.0 port on the standard iPhone 15 and 15 Plus. Hence, all the USB-C memory sticks mentioned in this article are also USB 3 compliant. The iPhone 15 Pro and Pro Max have USB 3.0 ports that support fast data transfer. Any of the best USB 3 flash drives for the iPhone 15 series mentioned below can do the job. However, you don’t necessarily need an SSD. In fact, Apple lets you record ProRes videos directly only to an SSD connected to your iPhone 15 Pro. As a result, you can plug in external accessories like docks, keyboards, mice, and SSDs. So, if you plan on transferring files from your desktop to your phone, a combo such as the Vansuny Dual flash drive is a must-have.Thanks to the almighty (and the EU), the iPhone 15 series of phones finally have USB-C ports. Not only is Type-A a touch more stable, but many laptops only have a single USB-C port, and most desktops don't have any. The USB-C connector is more robust than the obsolete micro-USB but a bit less sturdy than the full-size USB-A connector. One final note on PC-to-smartphone file transfer: for convenience, consider one of the multiple 2-in-1 flash drives highlighted. Ultimately, it's worth checking out PC benchmarks when comparing which drives are fastest in the real world, as testing on a PC removes potential bottlenecks such as low-speed USB ports on smartphones. The speeds you get depend heavily on the hardware and software in your smartphone or tablet. For example, the Samsung Galaxy S22 Ultra boasts 10 gigabits of throughput over its USB 3.2 Gen 1 port.Īll this is to say that a manufacturer's claims of maximum speeds should be taken with a grain of salt. If you're the proud owner of a high-end smartphone, a premium flash drive such as the Samsung MUF series or the Kingston Ironkey Vault can take full advantage of your device's cutting-edge hardware. Those numbers decrease if you're copying many small files or if the device gets extremely hot, at which point it may throttle to keep from overheating. When plugged into a PC, the average good-quality thumb drive can read and write at roughly 90-120 MB/s and 20-50 MB/s, respectively. If you frequently transfer files from your PC to your smartphone, opting for faster standards might help. PC file transfer: the reason to get a high-speed flash drive If your phone is one of those, consider whether it's worth investing in a high-performing USB 3.1 flash drive. Many of the best modern smartphones have USB-C ports but are still limited to USB 3.0 speeds. So what does that mean in terms of smartphones and tablets? Not much. All previous USB standards can work over USB-C, but having a Type-C plug doesn't guarantee that a device is capable of USB 3.1 or even 3.0 speeds. USB 3.0, 3.1, 3.2 Gen 2, as well as 3.2 Gen 1x2, 2x1, and 2x2 (yes, sadly, those are all real designations) all refer to the speeds the bus can transmit. To clear up any confusion, USB Type-C only refers to the USB-C connector, and that's it. At least, that's what it seems like sometimes. That's why we have protocols like USB Gen 2 2x2, which used to be simply called USB 3.2 but was renamed to confuse the average consumer. It's a little-known fact that the USB Implementers Forum is a group of global leaders hell-bent on ensuring that nobody will truly understand which USB standards are capable of which speeds. The worrying notion is supported by early predictions that indicate the album could sell as little as 125k its first week. Yet, while many are praising the singer/songwriter’s willingness to go against the grain of what most of today’s chart-toppers are offering, there is an eery lack of buzz surrounding the project. 0/5 Watch on Netflix How To Unblock Every Movie & TV Show on Netflix No Matter Where You Are. Decades later, trans historian Susan Stryker unearthed the history of the riot and interviewed the surviving Comptons queens. Gimmicky or daring? Some music lovers can’t decide. Surviving Compton: Dre, Suge & Michelle 2016 Action / Drama. Michel’le Toussaint, known professionally as just Michel’le, is the subject of Surviving Compton: Dre, Suge & Michel’le, a Lifetime movie that debuted on October 15, 2016.Toussaint had an. A clear answer to fans thanks to the overwhelming response to Mars’ 2014 knockout hit ‘Uptown Funk,’ ‘Magic’ almost acts as a full length version of ‘Funk’ in that almost every song on the project is sonically reminiscent of some of R&B’s most prized offerings from the late 80’s and early 90’s. The story of R&B artist Michelle, who rose to fame in the late 1980s when she signed on to Eazy-Es Ruthless Records. Titled ’24k Magic,’ the project – launched to charts on the backs of its title track (which skyrocketed to the Billboard Hot 100’s top 5) and its 90’s slow jam-inspired follow-up ‘Versace on the Floor’ – is a themed affair that gives music lovers a ride down music’s memory lane. Purchase Surviving Compton: Dre, Suge And Michelle on digital and stream instantly or download offline. It’s a point Amazon makes in Them: Covenant, the first season of its new anthology. Netflix giveth and Netflix taketh away As a new month rolls in, its time for Netflix to remove some titles from its database. November 18th brought with it the long-awaited third album from one of modern music’s eminent male performers – Bruno Mars. turned Compton into a rap mecca, the Southern California city was blindingly white. Thus, it can form one more bond and is reactive. Wilkinson's catalyst has 8 ligand electrons plus 8 metal electrons for a total of 16 electrons. It satisfies the 18 electron rule and is unreactive until it loses one or two ligands in solution. Tetrakis triphenylphosphine palladium has 8 ligand electrons plus 10 metal electrons for a total of 18 electrons. Thus, we can complete our analysis of the example complexes above. Rh is in group 9, so it has 8 valence electrons as a +1 metal. In Wilkinson's catalyst above, we determined it is Rh(I) which means Rh has lost one valence electron. It is in group 10 in the periodic table, so it has 10 valence electrons. In the Pd complex above, we determined it is Pd(0) which means Pd has all of its valence electrons. To determine the metal's valence electrons, we must look at the periodic table and factor in its oxidation state. In both of the complexes above, there are four sigma bonds from the ligands to the metals, so there are 8 electrons from the ligands. Ligand electron counting is as simple as counting the bonds from the ligands to the metal and multiplying by 2. 3) Add the ligand electrons plus the metal electrons. 2) The valence electrons from the transition metal based on its oxidation state. To do this, we must determine 1) The total electrons donated to the metal from the ligands. The next step is to detemine the total electron count around the metal to see if it satisfies the 18-electron rule. This means Rh has a +1 oxidation state: Rh(I). The metal must balance that charge so that the overall complex is neutral. In the Rh complex, the net charge on the ligands is negative one. So, in the Pd complex, the ligands have no formal charge, and Pd has a zero oxidation state: Pd(0). (Just like N, which is in the same column in the periodic table, P is neutral with 3 bonds and a lone pair.) Halogens with eight electrons and no bonds have a negative one formal charge. Phosphine ligands are common in transition metal complexes, and their charge is always neutral. Let's practice this by looking at a Pd complex (Pd(PPh 3) 4) and a Rh complex ((Ph 3P) 3RhCl). 4) The metal oxidation state balances the ligands' summed formal charges so that the overall complex is neutral (or negative if it's an anionic complex/positive if it's a cationic complex). 3) Add up the charges on all of the ligands. 2) Assign a formal charge to the ligand atoms bound to the metal using standard organic chemistry formal charge rules. To do this, we will 1) Consider the sigma bond electrons between the metal and the ligand as belonging to the ligand. First, we must determine the oxidation state (formal charge) of the metal. We will start by analyzing metal complexes where the ligands are bound to the metal via sigma bonds, like in tetrakis triphenylphosphine palladium above. Metals with high oxidation states are electron poor and are much more reactive than low oxidation state or neutral metal complexes. This is called the metal's oxidation state. Also, we need to learn how to determine the formal charge on the metal. For active catalysts, we must have metals that are surrounded by fewer than 18 electrons. Transition metal complexes containing 18 electrons are generally stable and unreactive. Instead, we add 10 electrons (because of the 5 d orbitals) and come up with the 18-electron rule. Transition metals have ready access to d-orbitals, so the octet rule does not apply. Much time in introductory organic chemistry is spent discussing the octet rule (based on filling s and p orbitals). |
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