Redo the above with 100 carbons-14 atoms and fill in the three boxes below How do the pie graph of 20 atoms compare to those of 100 atoms?_________ Generally, does the size of a radioactive sample affect half-life?________ Why/Why not?____________ Consider Uranium-218... Carbon-14's half-life was measured in thousands ($700) of years. About how long is Uranium-238's half-life?_________ How many protons does U-238 have?________ How many neutrons?________ Into what atom does Uranium-238 decay?__________ Does the sue of the sample of Uranium-238 affect its half-life?_________ About that unknown Element..... How would you determine the half-life of this unknown element' Write up a little plan here: Estimate the half-life of this element.________ seconds. Observe the decay curves (% remaining vs time) for Carbon-14 and Uranium-238. Sketch the decay curve for those isotopes here: Radioactive Dating Game
Calculate the average mass of each isotope by dividing the total mass by the number of particles of that isotope. Record your answers on the Data Table.
Calculate the percent abundance of each isotope by dividing its number of particles by the total number of particles and multiplying by 100. Record your answers on the Data Table.
Calculate the relative abundance of each isotope by dividing the percent abundance from Step 2 by 100. Record your answers on the Data Table.
Calculate the relative mass of each isotope by multiplying its relative abundance from Step 3 by its average mass. Record your answers on the Data Table.
Calculate the average mass of all Metallo particles by adding the relative masses. This average mass is the atomic mass of Metallo.
Explain the difference between percent abundance and relative abundance. What is the result when you total the individual percent abundances? The individual relative abundances?
The percent abundance of each isotope tells you how many of each kind of isotope exist in every 100 particles. What does relative abundance tell you?
Compare the total values for Rows 3 and 6 in the Data Table. Explain why the totals differ and why the value in Row 6 best represents the atomic mass.