Question

What property of water allows icebergs to float? Salt is excluded when water freezes and fresh water is less dense than salt water. The density of water increases with depth (due to the weight of the water above). Water is less dense as a solid (ice) than it is as a liquid. When ice is at the surface it will stay there.

Answer 1

Answer: Water is less dense as a solid (ice) than it is as a liquid.

When water freezes into it's solid form that is ice, it's molecules attain more stability in it's hydrogen bond. As, these hydrogen bonds attain their position rather remaining free as seen in liquid water. Due to this type of hydrogen bonding the ice attains a compact structure. The hydrogen molecules in ice are separated from each other, which were earlier closer to each other. Hence, structure of ice reduces it's density as compared to liquid water. Therefore, the property of water which allows icebergs to float is water is less dense as a solid than it is as a liquid.  

Answer 2

The reason is that ice is less dense than liquid water. Substances with density lower than water's will float in water, for example ice, oil, and wood. All that is assuming that icebergs are solid ice, and both icebergs and the sea are fresh pure water