Final answer:
To calculate the atomic mass of nitrogen the abundance of each isotope (N-14 and N-15) and their exact masses are required. the atomic mass is the weighted average of these isotopes' mass numbers, based on their relative abundance.
Step-by-step explanation:
To calculate the atomic mass of nitrogen, information about the abundance (percentage by number) of each isotope and the exact mass of these isotopes is necessary. Nitrogen has two main isotopes, nitrogen-14 (N-14) and nitrogen-15 (N-15). Since atomic mass is a weighted average, we first need to know the relative amounts of these isotopes in a typical sample of nitrogen. Then, these percentages are multiplied by the mass number of each isotope, and the results are summed to find the atomic mass of nitrogen.
For instance, if we were to find that 99.63% of nitrogen atoms were N-14 with a mass of approximately 14 amu (atomic mass units), and 0.37% were N-15 with a mass of approximately 15 amu, we would use these values to calculate nitrogen's atomic mass. the calculation would be: (99.63% × 14) + (0.37% × 15) = atomic mass of nitrogenIt is important to note that the atomic mass is not simply the arithmetic mean of the mass numbers of the isotopes but a weighted average based on the isotopic composition of the element on Earth.