Final answer:
Relative abundance of isotopes can be deduced from mass spectrometry peaks, with peak height indicative of abundance. Isotopes of an element have the same number of protons but differ in neutron count, as indicated by subtracting the atomic number from the mass number.
Step-by-step explanation:
To deduce the relative abundance of isotopes from a mass spectrum, consider the peaks' heights, as they usually correlate with isotope abundance.
In this case, the three peaks at m/z 158, 160, and 162 likely represent isotopes of an element (Zr, based on the provided figures), with the heights of these peaks being proportional to each isotope's natural abundance.
The peak at m/z 158 appears first and is typically the most abundant, followed by 160 and then 162, indicating a decrease in abundance. If 158 represents a 100% relative abundance peak, the relative heights of 160 and 162 can be compared to deduce their abundance relative to 158.
For example, if 160's peak height is half of 158's, its relative abundance would be roughly 50% of the isotope at 158. The three isotopes of oxygen mentioned are 16O, 17O, and 18O, with atomic numbers indicating all isotopes have 8 protons.
The difference in neutron count can be deduced by subtracting the atomic number from the mass numbers: 160 (16-8=8 neutrons), 170 (17-8=9 neutrons), and 180 (18-8=10 neutrons).