Verified answer

Calculate the number of moles of Y you have

Divide the mass by the number of moles to get the atomic mass.

Look at the periodic table to identify the element.

1 mol of Y contains 6.02*10^213 atoms

You have (3.72*10^22) / (6.02*10^23) = 0.0618 mol of Y has mass 1.50g

1.0mol Y has mass = 1.50/0.0618 = 24.27g/mol ( or 24.3g/mol to 3 sig figs)

Magnesium has molar mass 24.305g/mol

Conclusion :Element Y = Mg.

Calculate the mass of 6.02x10²³ atoms if 3.72x10²² atoms mass 1.50 g.

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