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An electron has a negative charge. When an atom loses an electron, it becomes a positive ion.
When an atom of lithium loses an electron and becomes an ion, it has one less electron shell, so its radius is smaller than the radius of the atom.
The answer is 3.
A likely application of a radioactive isotope with a short half-life such as Technetium-99 will be as a medical tracer. It will likely be used by a doctor to check the movement of substances within a person's body.
A radioactive isotope with such a long half-life like Rubidium-87 is likely used in the determination of the age of fossils and artifacts found by archaeologists.<span />
Answer:
carbon mass = 12.01g/mol
hydrogen mass = 1.01g/mol
4 carbon atoms and 10 hydrogen so
12.01 x 4 + 1.01 x 10
48.04g/mol + 10.10g/mol
= 58.14g/mol
