Percent Abundance Additional Practice (answers on next page)
1.The element Europium occurs in two common isotopes: Eu-151 and Eu-153. Use the average atomic mass of
Europium to calculate the percent abundance of each isotope.
__________________________ % abundance of Eu-151
__________________________ % abundance of Eu-153
2.Bromine has two isotopes: Br-79 and Br-81. Calculate the percent abundance of each isotope.
_________________________ % abundance of Br-79
_________________________ % abundance of Br-81
3.Gallium has 2 common isotopes: Ga-69 and Ga-70. Calculate the percent abundance of each isotope.
____________________% abundance of Ga-69
____________________% abundance of Ga-70
Percent Abundance Additional Practice
1.The element Europium occurs in two common isotopes: Eu-151 and Eu-153. Use the average atomic mass of
Europium to calculate the percent abundance of each isotope.
_______51.8%___________ % abundance of Eu-151
________48.2%__________ % abundance of Eu-153
2.Bromine has two isotopes: Br-79 and Br-81. Calculate the percent abundance of each isotope.
________54.8%___________ % abundance of Br-79
________45.2%___________ % abundance of Br-81
3.Gallium has 2 common isotopes: Ga-69 and Ga-70. Calculate the percent abundance of each isotope.
_____27.7%__________% abundance of Ga-69
_____72.3%_________% abundance of Ga-70