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Use this information to answer the next two questions: This graph indicates the melting range for mantle rock at different pressures (left) and the melting range for mantle rock in the presence of H2O (right). Image Description Image of two graphs. The graph on the left shows pressure (y-axis) versus temperature (x-axis). At the bottom right where temperature and pressure are low, the rock is all solid. The top right of the graph shows the rock as all liquid where temperature is high and pressure is low. Starting with low temperature and pressure, as you move toward greater temperature and pressure, a zone of melting runs from the top and bottom along the center of the graph. It starts where pressure is high and temperature is low and curves to the bottom right of the graph as temperature and pressure both increase. The graph on the right shows pressure versus temperature with water. At the bottom right where temperature and pressure are low, the rock is all solid. The top right of the graph shows the rock as all liquid where temperature is high and pressure is low. Starting with low temperature and pressure, as you move toward greater temperature and pressure, a zone of meltling with water cuts across the first half of the graph. It starts where pressure is high and temperature is low and stays in the melting zone as pressure increases and temperature stays low. As temperature gets higher alongside pressure, the meling zone with water curves to the bottom of the graph ending where you have medium temperature and high pressure.

Uranium-238 alpha decays, emitting a helium-4 nucleus. What is the mass number of the product?

Which of these fatty acids has a low melting point? (Which one would be likely to be a liquid at room temperature?)

An astronomer discovers brightly glowing disk of gas in space surrounding a neutron star, like the one pictured below. What would they say happened?    Attributions Images NASA, ESA, and Z. Levay (STScI); Radio: NRAO/AUI/NSF GBT+VLA 1.4 GHz mosaic (Dyer, Maddalena and Cornwell, NRAO); X-ray: NASA/CXC/Rutgers/G. Cassam-Chenai and J. Hughes et al.; Optical: F.Winkler/Middlebury College and NOAO/AURA/NSF; and DSS. Full-shell Image of SN 1006 Showing Location of Hubble Observations [photograph]. (public domain). Via NASA.

The wave model replaced the Bohr, modified solar system model of the atom because the wave model can explain and predict things when the Bohr model either fails to explain them or provides incorrect predictions. Which of the following is one of the reasons that the wave model is better than the Bohr model?

These experiments with electrons and slits told us something important about the nature of electrons. They tested and confirmed a new idea about electrons. What new information did we learn from these results?

What can you conclude from the cross-section below?  

When you compare saturated with unsaturated fatty acids containing the same number of carbon atoms, what is true?

When electrons are sent one at a time towards a pair of closely spaced slits and detected using a screen placed beyond the slits, they gradually build up a pattern like the one shown in the figure below.    Image Description a series of images showing dots on a screen. The first image appears to show random dots, but as they progress, and there are more dots, it is clear that the dots are grouped into vertical stripes separated by regions where there are almost no dots. Attributions Images Belsazar. Double-slit experiment results Tanamura 2 [photograph]. (CC BY-SA 3.0). Via Wikimedia Commons.

The next two questions deal with a stick of dynamite exploding.