#### Answer

The identity of $Y$ is the element Calcium, represented by $Ca$.

#### Work Step by Step

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).