Does sand sink or float in water?

Answer 1

Sand has a higher density than water and therefore it will sink in water. The density of sand varies depending on the type but is usually in the region of 2-3 g/cm3 compare to 1 g/cm3 for water.

Answer 2

Your question has a number of possible answers!

1) Sand is porous and permeable so if the water is free to drain then the sand will be only partially saturated (not all the pore space is filled with water). In these conditions the pore water pressure becomes negative (soil suctions develop) which can act to decrease the volume of the soil.

2) Soils have an optimum moisture content at which they can be compacted to their highest density. Too much moisture leads to the pore spaces being saturated and when you attempt to compact the soil to remove the air voids the (relatively) incompressible water filling the pores does not deform and so the volume remains the same. Conversely at low moisture contents the pore water pressures yield higher suctions making the soil shear strength higher in part due to the frictional resistance between the grains being increased and making the soil more difficult to compact. As moisture content increases so to does pore water pressure as the suctions dissipate. This reduces the inter-granular contact forces and so decreases frictional resistance to deformation. The optimum moisture content that allows the maximum decrease in volume will lie somewhere between these two moisture contents.

Answer 3

the particles in sand are thicker and heavier and they absorb the water,

Answer 4

sand sinks because it is more dense than water.

Answer 5

In still water, sand will tend to settle / sink. In faster flowing water, the water may have enough energy to transport sand without it sinking.

Answer 6

Sand sinks in water.