To find the mass of cobalt-60 in the given sample, we need to use the information given about the isotopes and their relative atomic masses. Here's how you can approach it step-by-step:
1. Determine the mass of cobalt-59 in the sample:
- Given that the relative atomic mass of cobalt-59 is 58.9332, we can assume that the entire sample consists of cobalt-59 atoms.
- Multiply the relative atomic mass of cobalt-59 by the mass of the sample:
Mass of cobalt-59 = 58.9332 * 1.8155 g
2. Determine the mass of cobalt-60 in the sample:
- Given that the relative atomic mass of cobalt-60 is 59.9338, we can assume that the difference between the apparent "atomic mass" of the sample (58.9901 g) and the mass of cobalt-59 will give us the mass of cobalt-60.
- Subtract the mass of cobalt-59 from the apparent "atomic mass":
Mass of cobalt-60 = (Apparent "atomic mass" of the sample - Mass of cobalt-59)
Using these steps, you can now calculate the mass of cobalt-60:
Mass of cobalt-59 = 58.9332 * 1.8155 g
Mass of cobalt-60 = 58.9901 g - (58.9332 * 1.8155 g)
By performing these calculations, you should be able to determine the mass of cobalt-60 in the given sample.