Question 23

Solids do not always sink in liquids; it depends on the density of the solid and liquid.

The behavior of solids in liquids is determined by their relative densities. If a solid is less dense than the liquid, it will float; if it is denser, it will sink. Therefore, the statement that solids will always sink is incorrect.

A) True, because solids are hard while liquids are not.

This option is incorrect because the hardness of a substance does not determine whether it will sink or float in a liquid. The critical factor is density, not hardness.

B) True, because solids are heavier than liquids.

This statement is misleading. While some solids are heavier than liquids, this does not universally apply to all solids and liquids. The sinking or floating of a solid is dependent on its density relative to the liquid, not merely its weight.

C) False, because solids have a smooth surface, so they will float.

This option is incorrect as it inaccurately attributes the ability to float to the smoothness of a solid's surface. The ability to float is based on the density of the solid compared to the liquid, not the texture of the surface.

D) False, it depends on the density of the solid and liquid.

This option is correct because whether a solid sinks or floats in a liquid is entirely dependent on the densities of the two substances. If the solid is less dense than the liquid, it will float; if it is denser, it will sink.

Conclusion

The correct answer is D, as it accurately reflects the principle that the floating or sinking of solids in liquids is contingent upon their respective densities. All other options fail to consider the fundamental role of density in this phenomenon, leading to incorrect generalizations about the behavior of solids in liquids.