At $20°C$, the density of copper is $8.9$ $g$$/$$cm^3$. The density of platinum is $21.4$ $g$$/$$cm^3$. What does this tell you about how the atoms are "packed" in each material?

Md Ariful Islam

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Md Ariful Islam

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$"Molar mass (Cu)"$ $=$ $63.55$ $g*mol^-1$.

$"Molar mass (Pt)"$ $=$ $195.08$ $g*mol^-1$.

This threefold difference in molar mass, of course translates to . Given that the difference in densities is (very approx.) threefold as well, we would predict that the atomic packing in both metals is similar in terms of , $"mass per unit volume"$. Does this make sense?

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