## Chemistry (7th Edition)

The identity of $Y$ is the element Calcium, represented by $Ca$.
1. Convert that number of atoms to moles: $2.26 \times 10^{22}$ atoms $\times \frac{1 mol}{6.022 \times 10^{23} atoms} = 0.0375$ mol. 2. Find the molar mass. $\frac{1.50g}{0.0375mol} = 40.0g/mol$ Since the molar mass is equal to the atomic weight, find the element in the periodic table with this value for its atomic weight. It is the Calcium (Ca).