What Energy Must Be Added or Given Off in a Reaction

question 69

Multiple Choice

What energy must be added or given off in a reaction where a helium atom is separated into two hydrogen atoms and two neutrons? (Atomic masses for each: hydrogen,1.007825 u;neutron,1.008665 u;helium,4.002602 u;also,1 u = 931.5 MeV/c². )

• A)28.3 MeV given off
• B)20.7 MeV added
• C)20.7 MeV given off
• D)28.3 MeV added

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Definitions:

K

The symbol for potassium, a chemical element with atomic number 19, essential for plant growth and functioning of the nervous system in animals.

pH

A measurement system that determines whether an aqueous solution is acidic or basic, scaling from 0 (highly acidic) to 14 (highly basic).

K

Potassium, a chemical element with symbol K, essential for living organisms and used in numerous industrial processes.

[HCO3-]

The chemical notation for bicarbonate, an anion that acts as a buffer in maintaining acid-base balance in biological systems.