Nickel has a lower atomic mass than cobalt, even though it has a higher atomic number. One possible explanation is that one of the average atomic masses was miscalculated. In the case of cobalt, there is only one isotope: 100% ⁵⁹Co at a mass of 58.9332 amu. For nickel, however, there are five isotopes as given in the table. $\begin{array}{|l|l|l|} \hline \text { Isotope } & \text { mass }(\mathrm{amu}) & \text { abundance } \ \hline{ }^{58} \mathrm{Ni} & 57.9354 & 67.76 \% \ \hline{ }^{60} \mathrm{Ni} & 59.9308 & 26.16 \% \ \hline{ }^{61} \mathrm{Ni} & 60.9311 & 1.25 \% \ \hline{ }^{62} \mathrm{Ni} & 61.9283 & 3.66 \% \ \hline{ }^{64} \mathrm{Ni} & 63.9280 & 1.16 \% \ \hline \end{array}$ Using the data in the table, what is the average atomic mass for nickel A) 60.45 amu B) 58.70 amu C) 59.75 amu D) 58.10 amu E) 59.25 amu

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The Answer of Nickel has a lower atomic mass than cobalt, even though it has a higher atomic number. One possible explanation is that one of the average atomic masses was miscalculated. In the case of cobalt, there is only one isotope: 100% ⁵⁹Co at a mass of 58.9332 amu. For nickel, however, there are five isotopes as given in the table. $\begin{array}{|l|l|l|} \hline \text { Isotope } & \text { mass }(\mathrm{amu}) & \text { abundance } \ \hline{ }^{58} \mathrm{Ni} & 57.9354 & 67.76 \% \ \hline{ }^{60} \mathrm{Ni} & 59.9308 & 26.16 \% \ \hline{ }^{61} \mathrm{Ni} & 60.9311 & 1.25 \% \ \hline{ }^{62} \mathrm{Ni} & 61.9283 & 3.66 \% \ \hline{ }^{64} \mathrm{Ni} & 63.9280 & 1.16 \% \ \hline \end{array}$ Using the data in the table, what is the average atomic mass for nickel A) 60.45 amu B) 58.70 amu C) 59.75 amu D) 58.10 amu E) 59.25 amu

Nickel Has a Lower Atomic Mass Than Cobalt, Even Though