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A college friend of yours who has been postponing taking any science courses hears you talking about the generation of nuclear energy in the Sun and makes the following observation: “The whole idea of the atomic nucleus is pretty ridiculous. If an oxygen nucleus consists of eight protons and eight neutrons, the charge on that nucleus is positive. Since even I learned in high school that like charges repel, such a nucleus would find all its positive protons repelling and quickly fall apart.” How would you answer his argument?

Radioactive dating techniques have revealed that our Earth and Moon are approximately how old?

During the process of differentiation,

An idealized object that does not reflect or scatter any radiation that hits it, but simply absorbs every bit of radiation that falls on it is called:

An astronomer observes two ordinary stars. The first one turns out to be twice as hot as the second. This means that the first one radiates:

A star is 230 light years away. The light we see tonight from that star left it

A compound with a molecular formula C5H11NO has the 1H NMR spectrum given. The IR spectrum shows an absorption at around 3400 cm-1. Which of the structures given is consistent with this spectrum? The number by each peak is the proton count for that peak.

A compound with a molecular formula C9H12 has the 1H NMR spectrum below.  Which structures given is consistent with this spectrum?  

Which of the compounds shown has an odd m/z value for the molecular ion?

Which one of the given compounds is consistent with the IR spectrum shown?