A radioactive element has an unstable nucleus that emits particles in the form of alpha, beta, or gamma radiation. A stable element has a nucleus that does not emit such particles
Answer:

Explanation:
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In this case, we can compute the required volume by using the ideal gas equation as shown below:

Thus, solving for the volume and considering absolute temperature (in Kelvins), we obtain:

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Answer:
228 mL
Explanation:
M1*V1 = M2*V2
M1 = 6.58 M
V1 = ?
M2 = 3.00 M
V2 = 500 mL
V1 = M2*V2/M1 = 3.00M*500.mL/6.58 M = 228 mL