When a Stationary Plutonium-239 $\begin{array} { c } 239 \\94\end{array}$ Pu, Decays into Uranium-235 Plus an Alpha Particle, the Energy

question 9

Multiple Choice

When a stationary plutonium-239, $\begin{array} { c } 239 \\94\end{array}$ Pu, decays into uranium-235 plus an alpha particle, the energy released in the process is 5.24 MeV. The following masses are known: $\begin{array} { l } 4 \\2\end{array}$ He: 4.002603 u $\begin{array} { c } 235 \\92\end{array}$ U: 235.043924 u What is the mass of the $\begin{array} { c } 239 \\94\end{array}$ Pu nucleus, in amu? (1 u = 931.494 MeV/c²)

• A)239.05215 u
• B)239.02775 u
• C)239.00189 u
• D)238.99919 u
• E)238.98884 u

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Definitions:

Unfreezing

The initial stage in the change process where existing patterns or behaviors are challenged in preparation for change.

Refreezing

The process of stabilizing a group, organization, or system after a change has been implemented, ensuring the new state is maintained.

Attitude-centered

Orientation that focuses on the attitudes and mindsets of individuals as pivotal elements in achieving outcomes.

Role-centered

An approach or perspective that focuses on the importance of defined roles and responsibilities within an organization or system for effective functioning and achievement of goals.