When a substance has a density less than that of water, what will happen when it is placed in water?

• A. It will sink to the bottom of the water.
• B. It will dissolve completely in the water.
• C. It will remain suspended in the middle of the water.
• D. It will float on the surface of the water.

Answer: (D)

Verified step by step guidance

1. Recall the definition of density: density is mass per unit volume, expressed as \(\rho = \frac{m}{V}\).
2. Understand that water has a density of approximately 1.00 g/cm³ at room temperature.
3. Compare the density of the substance to that of water: if the substance's density is less than water's density, it means the substance is less dense and therefore lighter per unit volume.
4. Apply the principle of buoyancy: an object less dense than the fluid it is placed in will experience an upward buoyant force greater than its weight, causing it to float.
5. Conclude that since the substance has a density less than water, it will float on the surface rather than sinking, dissolving, or remaining suspended.