The property of water that makes icebergs float on is due to the fact that <u>water as a liquid is denser than as a solid</u>.
According to the rules of floatation,<em> a less dense substance will always float on a denser liquid because a body will always displace its own weight when placed in a liquid</em>. At room temperature, water as a liquid has a density of 1 g/cm3 but if the same water forms ice, the density would be 0.92 g/cm3. Hence, when ice is placed on water, it will float on it.