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Just How Small Is an Atom?

Just How Small Is an Atom?
Whether we’re zooming in to the wavelength of a gamma ray or zooming out to the size of a galaxy, it can be difficult to wrap our heads around the big numbers we’re measuring—like nanometers (10-9meters) or gigameters (109). Take a look at these efforts to represent big numbers. What are the strengths of each? How would you represent a large number (like a gigameter)?

Uniones químicas I - Química Antes de analizar los tipos de uniones químicas, en necesario entender algunas propiedades de los elementos, como la Electronegatividad. Ésta, se define como la capacidad relativa de un elemento, para atraer electrones en una unión, es decir, se define en una unión de elementos, quién atrae a quién. Los niveles de electronegatividad, se definen a partir, de la regla del octeto. Esta regla, tiene una relación directa, con la independencia de los gases inertes, respecto al resto de los elementos Analizado su CEE, notamos, que en todos, es nS2 NP6, significa así, que su último nivel de energía está completo, con 8 electrones totales, siendo esto, a lo que aspiran el resto de los elementos, para lo cual, tienden a combinarse. Las uniones químicas, se clasifican según la diferencia de electronegatividad, de los elementos que participen, en una unión. Cuando la diferencia es grande, se da una unión Iónica. Otro tipo de unión es la covalente, que se da entre elementos, de alta electronegatividad.

Something surprising happens to your body when you freedive Featured image: Photo of freediver Hanli Prinsloo by Annelie Pompe. In 1949, a stocky Italian air force lieutenant named Raimondo Bucher decided to try a potentially deadly stunt off the coast of Capri, Italy. Bucher would sail out to the center of the lake, take a breath and hold it, and free-dive down one hundred feet to the bottom. Waiting there would be a man in a diving suit. Scientists warned Bucher that, according to Boyle’s law, the dive would kill him. Boyle’s law, which science had taken as gospel for three centuries, appeared to fall apart underwater. Bucher’s dive resonated with a long line of experiments — most of them very cruel and even monstrous by modern standards — that seemed to indicate that water might have life-lengthening effect on humans and other animals. He started the experiment by leading volunteers into an enormous water tank and monitoring their heart rates as they dove down to the bottom of the tank. This discovery was as important as it was surprising.

Peso Atomico Promedio (PA) | Quimica | Quimica Inorganica Representa la masa o peso atómico relativo promedio del átomo de un elemento. Es un promedio ponderado de las masas atómicas relativas de los isótopos de un elemento. La ponderación de hace con las abundancias naturales de los isótopos. Fórmula general para evaluar el PA de un elemento “E” con “n” isótopos: Donde: m1 = masa atómica relativa del primer isótopo m2 = masa atómica relativa del segundo isótopo m3 = masa atómica relativa del tercer isótopo a1 = abundancia natural del primer isótopo a2 = abundancia natural del primer isótopo a3 = abundancia natural del primer isótopo Ejemplos: 1. Reemplazando en la fórmula: P.A. 2. Solución: Armamos nuestra tablita como sigue: Reemplazamos en la fórmula: P.A. Pesos Atómicos: Los pesos atómicos o masas atómicas relativas promedio se encuentran en toda tabla periodica, en todos los casos que se necesite los pesos atómicos solo bastará con ver la tabla periódica, no se necesita que se memorizar.

The Mistaken Assumptions That Changed Physics History - The Nature of Reality “Don’t assume,” they always say. Last month, Avi Loeb, an astrophysicist at Harvard, published an essay on how mistaken assumptions have delayed the progress of astronomy. In the same spirit, I wanted to find out how the course of physics has been influenced by assumptions, acknowledged or otherwise. Can lessons from the past help us be more aware of the assumptions we bring to physics today? Is it desirable—or even possible—to work without assumptions? In the years after scientists came to accept light as a wave, brilliant researchers spent untold hours chasing after the “ether,” hypothetical stuff through which light waves were thought to propagate. If Einstein resolved one roadblock, he set up another. Dice or no dice? It’s hard to imagine an astronomer dismissing observational data on the evidence of her “instinct for astronomy,” which highlights a key difference between the two fields. Hidden assumptions can also live at the heart of how we do science.

Understanding the Atom The 2,400-year search for the atom - Theresa Doud Ernest Rutherford Although Ernest Rutherford is well known for his discovery of the nucleus, he did a lot of other research and experiments into topics other than the atom. He started his career studying electricity and magnetism and it wasn’t until he left his home of New Zealand and moved to Cambridge, England that he started working with the atom. Working under J.J. In 1911 after returning to England, Rutherford conducted his most famous experiment with alpha particles and gold foil which lead to his discovery of the nucleus. Where are the Electrons? After Rutherford discovered the nucleus, Neils Bohr (another of J.J. When Schrodinger’s equation is solved it does not give the exact location of an electron around a nucleus but as Max Born (yet another student of Thomson) discovered, it gives a probability density or area where the electron might be found. Schrodinger later went on to come up with a thought experiment or paradox that is referred to as Schrodinger’s Cat.

Structure of the Atom 1: The Earliest Models How do you know you exist? - James Zucker | TED-Ed René Descartes believed that most of what he acquired and learned came from the senses, but his senses had deceived him in the past. Can you give an example of when your senses have deceived you? Is there an experience that has made you doubt what you have seen or heard? Could this give you reason to doubt EVERYTHING you have learned from your senses? Descartes believed that if you doubt your own existence, you must exist to doubt it! René Descartes was an extremely talented man. Some famous quotes from Descartes are written below. “If you would be a real seeker after truth, it is necessary that at least once in your life you doubt, as far as possible, all things.” “Let whoever can do so deceive me, he will never bring it about that I am nothing, so long as I continue to think I am something."

CIAAW: Commission on Isotopic Abundances and Atomic Weights How Does the Brain Learn Best? Smart Studying Strategies In his new book, “How We Learn: The Surprising Truth about When, Where, and Why It Happens,” author Benedict Carey informs us that “most of our instincts about learning are misplaced, incomplete, or flat wrong” and “rooted more in superstition than in science.” That’s a disconcerting message, and hard to believe at first. But it’s also unexpectedly liberating, because Carey further explains that many things we think of as detractors from learning — like forgetting, distractions, interruptions or sleeping rather than hitting the books — aren’t necessarily bad after all. Society has ingrained in us “a monkish conception of what learning is, of you sitting with your books in your cell,” Carey told MindShift. “How We Learn” presents a new view that takes some of the pressure off. Getting to Know Your Brain’s Memory Processes In an interview, he highlighted three take-home messages from his book: Forgetting isn’t always bad. The brain is a foraging learner. For example:

IDTIMWYTIM: Heisenberg Uncertainty Principle