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This diagram depicts the energies of a few shells (energy levels) for the atom that produced the spectrum above. Image Description Diagram of five lines to represent energy levels drawn horizontally. N=1 is at the bottom and n=5 is at the top. Starting from the top, the line n=5 is shown. Moving downward, there is a small gap between the lines n=5 and n=4, a slightly larger gap between n=4 and n=3, an even larger gap between n=3 and n=2, and a very large gap is shown between n=2 and n=1. Which of the following situations would cause the atom to emit the highest frequency photon?

In an early experiment that helped determine the nature of atoms, gas was enclosed in a long, narrow glass tube. A metal plate near one end of the tube was given a large positive charge, and a plate at the other end was given a large negative charge. The particles that collected at each end of the tube were studied. Thomson’s plum pudding model was developed as a result of these experiments. What was discovered about atoms as a result of these experiments?

If microwaves were used instead of visible or UV light, what would be observed?

In the first half of the 1900s, the Bohr model was abandoned in favor of the quantum mechanical (wave) model of the atom. The next two questions test your understanding of the quantum mechanical model of the atom.

What is the distance between two successive light areas called? The distance is labeled 1 on the picture.

In the picture, a sound wave moves from the top of the page towards the bottom and passes through a small hole in a barrier (point 2 on the diagram). The light areas represent regions of low pressure, and the dark areas represent high pressure. The following questions ask you to use your understanding of wave behavior to explain what is happening at certain points.    Image Description The image shows horizontal evenly spaced bands of dark and light that extend from the top to a barrier with a hole at the bottom. The distance between two adjacent white bands is labeled 1, the hole is labeled 2. In the next three questions, use your understanding of wave behavior to explain what is happening at certain points.

In an important experiment used to determine the nature of atoms, a gas like hydrogen, neon, or mercury is excited by sparking it with electricity. The light emitted is separated out into individual colors using a prism or diffraction grating and a few lines of colored light are seen. The next three questions deal with your understanding of the mechanism behind these discrete spectra.    Jkasd, CC BY 3.0 , via Wikimedia Commons Image Description The image shows a dark black horizontal rectangle with thin colored lines spread out on it. There are magenta and purple lines on the left side, then moving right, blue, shades of green, one yellow line further away, and one red line fully on the right side. 

Which statement correctly describes the relationship between evolution and natural selection?

Examine the tree below. For the pairs of species listed below, select the node (the letter) that is their most recent common ancestor. 1) Dinosaurs and Fish: the most recent common ancestor is [node1] 2) Other Birds and Mammals: the most recent common ancestor is [node2] 3) Amphibians and Mammals: the most recent common ancestor is [node3]

A “Jaglion” is the offspring between a male Jaguar and a female Lion. Jaglions have only been born in zoos and animal sanctuaries. Jaglions are able to live to adulthood. It is unknown whether Jaglions are able to produce viable, fertile offspring. If researchers find that Jaglions produce offspring that cannot reproduce, would you conclude that Jaguars and Lions are the same species or different species? Remember the definition of species that we discussed in class and in the pre-class video.