Why do I despise high school chemistry? Because it's described in the antiquated terms of early 20th century science. I'm talking about you, Avogadro constant . I was tutoring my son this week when I came to a realization - we don't need the Avogadro constant anymore . It was useful before the existence of the atoms and molecules were established. But in 2007, we know about matter at the atomic and molecular scale, so we should stop replacing the concrete picture of subatomic particles, atoms and molecules with the (in)convenient ideas implied when we talk about moles of material. The Avogadro constant is really just a bad approximation of one divided by the mass of the proton. It's a bad approximation because instead of using the actual mass of the proton to calculate the constant, the accepted value is one twelfth the mass of a carbon 12 atom. The error comes about for several reasons. For one thing, there are twelve particles in the nucleus of carbon 12, but only hal
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