Situation:
You have 100ml of isotopically labelled water 3H2o. That is, the water is made with the radioactive isotope of hydrogen, tritium, 3H. Compounds that contain radioactive isotopes are called "hot." You pour this 100 mL of "hot" water into the ocean and allow it to thoroughly mix.
Question:
After the "hot" water mixes thoroughly with the ocean water, you remove 100mL of ocean water. How many molecules of 3H2o do you expect there to be in this 100mL sample. (Ignore any radioactive decay of the tritium)
its 21, Duh.
Does anyone know or have any idea how I should go about solving that question??
To determine the number of molecules of isotopically labeled water (3H2O) after mixing with the ocean water, we need to consider the concept of dilution.
When the 100 mL of "hot" water is poured into the ocean and allowed to mix thoroughly, it will distribute evenly within the entire volume of the ocean. This means that the concentration of the isotopically labeled water will become the same as the concentration of the ocean water.
Given that the initial volume of the isotopically labeled water is 100 mL and it mixes with the entire volume of the ocean, we can assume that the resulting concentration of the isotopically labeled water is now evenly distributed throughout the entire ocean. This essentially means that the concentration of the isotopically labeled water becomes undetectably low compared to the vast volume of the ocean.
Therefore, when you remove 100 mL of ocean water, the expected number of molecules of 3H2O in that 100 mL sample would be extremely small or effectively zero.