Density equation | Middle school chemistry | Khan Academy

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Density measures how tightly matter is packed into a given space, calculated by dividing mass by volume (D = m/V). Knowing a substance’s density can help identify it. For irregular objects, scientists often measure volume using water displacement, where the volume change in water shows the object’s volume. Combining this measurement with the object’s mass provides a way to identify materials accurately regardless of their shape.

00:00 Introduction
00:30 Density formula
00:57 Calculating Density example 1
02:15 Calculating Density example 2
03:35 Finding volume of irregular shapes
04:52 Is the key made of gold?
06:04 Summary

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