Hello, I'm an expert in material science with a focus on the properties of various elements and compounds. When comparing the weight of two substances, we typically look at their density, which is the mass per unit volume.

Gold is heavier than iron. The density of gold is approximately 19.32 grams per cubic centimeter (g/cm³), while the density of iron is about 7.87 g/cm³. This means that for the same volume, gold will weigh more than iron due to its higher density.

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So each gold atom weighs almost four times as much as each iron atom. The extra electrons in the gold atoms do make the atom a little bigger than an iron atom, but not a whole lot. So there are nearly as many gold atoms as iron atoms per volume, but each gold atom weighs a lot more. So gold ends up denser.read more >>