Pb has an average atomic mass of 207.19amu. The three major isotopes of Pb are Pb−206(205.98amu); Pb−207(206.98 amu) and Pb−208(207.98 amu). If the isotopes of Pb −207 and Pb−208 are present in equal amounts, calculate the percentage abundance of Pb−206, Pb−207,  Pb−208

29. Vanadium has two naturally occurring isotopes, 0V with an atomic mass of 49.9472 amu and 51V 9.9472 amu and 51V with an atomic mass of 50.9440. The average atomic mass of vanadium is 50.9415 amu. The calculated percentage abundance of the two isotopes are 5

Calculate the atomic mass of silicon. The three silicon isotopes have atomic masses and relative abundances of 27.9769 amu (92.2297%), 28.9765 amu (4.6832%) and 29.9738 amu (3.0872%). Copper used in electric wires comes in two flavors (isotopes):^63 Cu and^65 Cu.^63 Cu has an atomic mass of 62.9298 amu and an abundance of 69.09%. The other isotope, ^65 Cu, has an abundance of 30.91%. The average atomic mass between these two isotopes is 63.546 amu. Calculate the actual atomic mass of^65 Cu. Magnesium consists of three naturally occurring isotopes. The percent abundance of these isotopes is as follows:^24 Mg (78.70%), ^25 Mg (10.13%), and^26 Mg (11.7%). The average atomic mass of the three isotopes is 24.3050 amu. If the atomic mass of^25 Mg is 24.98584 amu, and^26 Mg is 25.98259 amu, calculate the actual atomic mass of^24 Mg. Antimony has two naturally occurring isotopes. The mass of antimony-121 is 120.904 amu and the mass of antimony-123 is 122.904 amu. Using the average mass from the periodic table, calculate the abundance of each isotope.