The activity of a sample of 35(upper#) 16(lower#)Sulfer (T 1/2= 7.55x10^6 s) is 2.51x10^5 decays per second.

WHat is the mass of the sample?

m= in grams

PLease help me out...Thank you! :)

To find the mass of the sample, we need to use the concept of radioactive decay and the half-life of the isotope.

The activity of a radioactive sample is defined as the rate at which radioactive decays occur, measured in decays per second (dps). In this case, the activity of the sample is given as 2.51x10^5 dps.

The activity of a radioactive substance can be related to the number of radioactive nuclei present in the sample and the decay constant (λ) using the equation:

Activity = λ * N

Where N is the number of radioactive nuclei.

The decay constant (λ) can be calculated using the formula:

λ = ln(2) / half-life

In this case, the half-life of 16Sulfer is given as 7.55x10^6 seconds. Plugging in the values, we can calculate the decay constant:

λ = ln(2) / (7.55x10^6 s)

Next, we need to find the number of radioactive nuclei (N) in the sample. The number of radioactive nuclei can be related to the mass of the sample (m), the molar mass of the isotope (M), and Avogadro's number (NA) using the equation:

N = (m / M) * NA

The molar mass of sulfur (16Sulfer) is 32.06 g/mol. Plugging in the values, we can calculate the number of radioactive nuclei.

Finally, rearranging the equation for activity, we can solve for the mass of the sample (m):

m = (Activity / (λ * NA)) * M

Plugging in the known values, we can calculate the mass of the sample in grams.

I hope this explanation helps you understand the steps involved in solving the problem. If you have any further questions, please feel free to ask.