Use the equation to complete the activity.

Question

219 86Rn→215 84Po+α 86219Rn→ 84215Po+α
The nuclear equation shows the transmutation of a form of radon into polonium and an alpha particle. In one to two sentences, explain whether or not the reaction is balanced.
written response

Scientists used to believe that chemical reactions fueled the sun. Why did this lead them to believe that the sun was very young? What kind of reactions do we now think are responsible for the energy released by the sun? In one to two sentences, explain your reasoning.
written response

Use the equation to answer the prompt.
10 6C→10 5B+ 0+1e 610C→ 510B++1 0e
A student claims that the equation models beta-minus decay because the atomic number of the nucleus decreases by one. In one or two sentences, explain the error in the student's reasoning.
written response

Answer 1

First Activity: Balancing the Nuclear Reaction

The nuclear reaction \(^{219}{86}\text{Rn} \rightarrow ^{215}{84}\text{Po} + \alpha\) is balanced because both the mass numbers and atomic numbers are conserved. On the left side, the total mass number is 219 and the atomic number is 86; on the right side, the mass number (215 from Po and 4 from α) adds to 219, and the atomic numbers (84 from Po and 2 from α) add to 86.

Second Activity: Energy Sources of the Sun

Scientists initially believed that chemical reactions fueled the sun because these reactions are relatively quick and would imply that the sun was young, as it would have consumed its fuel rapidly. However, we now know that nuclear fusion, particularly the fusion of hydrogen into helium, is responsible for the sun's energy, a process that occurs over billions of years and allows the sun to shine for a much longer time.

Third Activity: Error in Reasoning about Beta-Minus Decay

The student's claim that the equation models beta-minus decay is incorrect because, while the atomic number decreases by one, the equation does not appropriately account for the emitted beta particle, which is actually a negatively charged electron. Therefore, the correct representation should show the inclusion of this particle, emphasizing that one neutron is converted into a proton, resulting in an increase in atomic number rather than a decrease.