Question

The model of the atom evolved over time as scientific investigations uncovered new properties and observations about the atom. Describe the function of a model in scientific investigations.

Answer 1

A model is a visual that can be used to represent something too small, complex or big. It helps you understand what something's structure is like, and how it works.

Answer 2

In chronological order of development, use the Dalton model, followed by Chadwick, then Rutherford, the Bohr, and lastly Schrodinger. Read up about them and follow their models

Answer 3

A model is just a set of interlocking assumptions and principles that can be used to deduce facts that can be observed. It *may* be something that can be visualized, but it need not be. Don't confuse a scientific model with a model airplane. The only similarity is that the model airplane can be used to deduce things about the real airplane, e.g. that if you hold it between you and the sun, it will cast a cross-shaped shadow.

A scientific model, however, can be completely abstract. For example, I could have a model of human behaviour which says that whenever someone has a difficult problem, their gratitude at someone else helping them rises steadily with how long they have been frustrated. More frustration = more gratitude. That's a model. It makes definite predictions which can be empirically tested, so that I can determine whether the model is correct or not. We say it's a "model" because it allows me to predict something about human beings, but it is not, itself, a human being. In the same sense, a scientific model of the atom is something that lets me make predictions about real atoms, but it is not an atom itself.

The phrase "scientific model" and "scientific hypothesis" are almost synonymous. The only real distinction is that a model often contains a number of interlocking hypotheses. That means it is possible for one hypothesis that is part of the model to be disproved, but for the model to live on, modified.

The atom is a good example of this: the Thomson model of the atom contained electrons, consistent with Thomson's experimnts, embedded in a positively-charged jelly. Rutherford's experiments proved that the jelly part was false -- could not be true. So he replaced the Thomson model with his own, in which you had a hard tiny nucleus plus orbiting electrons. This isn't completely throwing away the Thomson model -- notice the electrons are kept -- but part of it, the nature of the positively-charged content, is changed. That's because the model of the atom consists of several hypotheses that connect: the nature of the nucleus, the nature of the electrons, and so forth.

Answer 4

Oops, mistake in my answer. It should be Dalton model, followed by THOMSON*, then Rutherford, the Bohr, Schrodinger then Chadwick.