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Table salt is made of sodium (Na) and chlorine (Cl). According to Bohr’s model, why does sodium tend to form a +1 ion?

Rutherford’s gold foil experiment showed that

What do greenhouse gases do as part of the greenhouse effect?

Use the following scenario to answer questions 1-5 A hospital is preparing a batch of radioactive isotopes to use in medical imaging. The isotope Technetium-99m (Tc-99m) is commonly used because it has a short half-life and gives off gamma radiation that can be detected by scanners without causing long-term harm. A chemistry student working in the lab needs to review atomic structure to make sure they understand how isotopes and atoms differ.

Balance the nuclear equation by determining the missing particle(s). Include mass number (A, superscript) and atomic number (Z, subscript). 3890​Sr →  ? ?  ​+   −10​e

Hospitals use Technetium-99m in imaging because it emits gamma radiation but decays quickly. What type of nuclear change is happening when Tc-99m gives off radiation?

The _________ was added to the Constitution to decrease the voting-age from 21 to 18.

To deal with a recession, proponents of supply side economics would recommend decreasing taxes on corporations. 

Which of the following is NOT a permanent member of the U.N. Security Council?

Proportional representation tends to result in a two-party system.