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Tung Phan

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First xenon compound

In 1962, the first compound of any “inert gas” was made by Neil Barlett by reacting platinum hexafluorideand xenon to form XePtF6, a yellow-orange solid that was stable at room temperature. The previous autumn, he had prepared a remarkable compound of oxygen with platinum hexafluoride. In that compound, [O2]+[PtF6]–, the platinum hexafluoride, PtF6 was such an extreme oxidizer that the oxygen formed a positive cation. Interestingly, the energy to remove an electron from oxygen (12.2 eV), he realized, was extremely close to that for xenon (12.13 eV). This suggested a xenon compound could be made in a similar way. His success ended the half-century belief that xenon was an inert gas, and is since known as a “noble” gas.«

Math Teacher

The night before one exam, two students tied one on, (well, actually, tied two on, one each), and managed to sleep through the final. They realized they were in serious trouble, so they agreed to tell the professor that they had a flat tire on the way to the exam.
``No problem." said the Professor, ``Come by my office at 5 P.M. and I'll give you the exam then."
Feeling pretty clever, the students spent the intervening time getting information on the exam from students who had already taken it, and making sure they knew how to do the problems. Coming to the professor's office that evening, they were told, ``Leave your books in my office, and I'll put you in two separate rooms for the exam." They were both ecstatic to see that the Professor had given them the exact same exam taken by the class that morning. However, there was an additional page tacked on the end, upon which was written, "For 50% of the grade, which tire was flat?"    

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