If the ice were to sink as it froze entire lakes would freeze solid. Water has some unique thermal properties.
Why Water Is More Dense Than Ice
For most substances density increases as temperature decreases.
Is ice denser than water. No water and ice do not weigh the same. Any ice that forms will float to the surface and be melted by the sun. But when we are talking about water something else happens.
However peak density of water occurs in water at around 4 o C and decreases at temperatures both above and below this see Figure 1. This process would continue until there were only a relatively thin layer of water in the more temperate zones. Because ice is less dense than the underlying water it floats.
You touched on the answer to why when you ask if ice would sink. Water is denser than ice. As ice displaces the heavy weight water it floats on the top of water.
The regular arrangement of oxygen atoms will give a lattice structure to the water known as ice. Ponds or lakes begin to freeze at the surface closer to the cold air. That is something you can weigh.
Thus the liquid form of water although engaged in transient hydrogen bonding is not as open and expanded as when held into its solid form by the rigid semi. The reason behind water having a more substantial volume than ice is that water occupies less space than ice. Ice is less dense than water and the pro.
Humm well lets first understand that a ton of water weighs the same as a ton of ice and the same as a ton of cotton. In other words ice takes up about 9 more space than water so a liter of ice weighs less than liter water. That is anomaly of water.
The density of ice is 09167 09168 gcm 3 at 0 C and standard atmospheric pressure 101325 Pa whereas water has a density of 09998 0999863 gcm 3 at the same temperature and pressure. When water is kept under different states like solid water and gas the volume varies as per the density and weight of the water. NO ice is not heavier than water.
The anomalous properties of water are those where the behavior of liquid water is quite different from what is found with other liquids. For example if we take the same volume of water and ice in the same container water would weigh more than ice. What you might be asking is why is ice DENSER than water.
The additional space created reduces the density of the water as it freezes making ice less dense than water. Water is unusual in that its maximum density occurs as a liquid rather than as a solid. Ice is less dense than liquid water and so it floats.
Ice floats because it is about 9 less dense than liquid water. The density of water is 1gmL. Hydrogen bonding make ice less dense than liquid water.
If you weigh the same volume of water and ice in a container then you will notice that the volume of water weighs more than that of ice. The density of ice is 09 gram per centimetre cube. This means ice floats on water.
The density of ice is 06gmL. It is found that ice occupies 9 percent more volume than water and hence it weighs lesser than water. If ice was denser than water life would not exist on this planet.
Solid water or ice is less dense than liquid waterIce is less dense than water because the orientation of hydrogen bonds causes molecules to push farther apart which lowers the density. When water freezes water molecules form a crystalline structure maintained by hydrogen bonding. Density of ice is lower than water.
The heavier water displaces the lighter ice so ice floats to the top. Because ice is less dense than water the deep oceans can never freeze even below zero degrees because to freeze they would have to expand and the pressure prevents this. The solid form of most substances is denser than the liquid phase thus a block of most solids will sink in the liquid.
Clearly once this crystaline structure is no longer forced into place by the rigid hydrogen bonding in ice it can collapse into itself resulting a greater density of water molecules. This is important because it allows ice to float above water. If the water cools below 4 degree C the hydrogen bonds are adjusted to bind with the oxygen atoms.
When water is frozen into ice the change in temperature creates excess hydrogen bonds between water molecules that increase the space between the molecules. Water has a different molecular dependency and forms. Well the truth is its not.
It insulates the water during cold seasons so that marine life will not have an over-cool environment hence allowing them to survive. This produces a crystal lattice commonly known as ice. As ice is less dense than water it floats.
The reason is that water is denser than ice and the space it occupies is less as compared to that occupied by ice. A layer of ice forms but does not sink as it would if water did not have this unique structure dictated by its shape polarity and hydrogen bonding. If ice were denser than water it would sink and the layer on top would freeze and sink.