Answer
a. I-127
b. P-31
c. U-326
d. Ar-22
Work Step by Step
1. Calculate the mass number for each isotope:
a. A = 53 + 74 = 127
b. A = 15 + 16 = 31
c. A = 92 + 234 = 326
d. A = 18 + 22 = 40
2. Write the isotopic symbol, using mass number after the symbol.
a. I-127
b. P-31
c. U-326
d. Ar-22
** Consult Figure 4.9, page 102, to see the symbols and atomic numbers for each of these elements.