M&M Isotope Lab Answer Key
Question: isotopes are
Answer: atoms of the same chemical element, each having a different mass number (neutrons).
Question: Isotopes differ in _____________ ______________ but never in ____________ ____________
Answer: mass number, atomic number
Question: the m&ms represent
Answer: atoms
Question: the purpose of this lab is
Answer: to calculate the average atomic mass using m&m’s and to observe the difference between isotopes.
Question: isotope #1
Answer: plain m&ms
Question: isotope #2
Answer: peanut m&ms
Question: average mass=
Answer: total mass/ # of m&ms
Question: % abundance=
Answer: # of each type of m&m/ total # of all m&ms x 100
Question: average atomic mass=
Answer: (mass of isotope 1)(% abundance) + (mass of isotope 2)(% abundance)…/100
Question: why is it important to zero out the paper towel when weighing the mass of the m&ms
Answer: the paper towel could add weight to the calculations