What happens to the mass of a sample containing a radioactive element during its half-life?
A. The mass decreases by half.
B. The amount of mass is doubled.
C. Eventually there is no mass at all.
D. The mass remains the same.
Of course, the mass remains the same for practical purposes. During the release of energy, a very tiny portion of mass is converted to energy, but that mass is extremelyl small, and cannot be determined by ordinary means.
What happens to the mass of a sample containing a radioactive element during its half-life?
The correct answer is A. The mass of a sample containing a radioactive element decreases by half during its half-life.
To understand why, let's first clarify what a half-life is. The half-life of a radioactive substance is the amount of time it takes for half of the substance to decay or transform into another element or isotope. This decay process is random and occurs at a constant rate.
During each half-life, half of the original radioactive atoms decay, while the other half remains unchanged. Therefore, as the radioactive atoms decay, the number of radioactive atoms decreases, leading to a decrease in the mass of the sample.
To calculate the mass remaining after a specific number of half-lives, multiply the original mass by (1/2) raised to the power of the number of half-lives. For example, if a sample has an original mass of 100 grams and undergoes two half-lives, the remaining mass would be 100 grams * (1/2) * (1/2) = 25 grams.
So, during each successive half-life, the mass decreases by half.