Calcium-39 Undergoes Positron Decay

question 89

Multiple Choice

Calcium-39 undergoes positron decay. Each positron carries 5.49 MeV of energy. How much energy will be emitted when 0.00250 mol of calcium-39 decays? (1 MeV = 1.602 × 10^-13 J)

• A) 13.2 kJ
• B) 1.32 × 10⁴ kJ
• C) 1.32 × 10⁶ kJ
• D) 1.32 × 10⁹ kJ
• E) None of these choices is correct.

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Definitions:

S-waves

Secondary or shear waves that travel through the body of the Earth during an earthquake, moving material perpendicular to the wave's direction of travel and cannot pass through liquids.

P-waves

Primary waves that are the fastest type of seismic waves, capable of moving through both solid and liquid layers of the Earth.

Surface Waves

Seismic waves that travel on Earth’s surface.

Subduction Zone

A region of the Earth's crust where one tectonic plate moves under another, often leading to volcanic activity and earthquakes.