Ice, like other solids will expand with heat. It has a coefficient of expansion of 50 ppm/°C.
So, the colder the ice is, the smaller, and higher density it will be. The warmer, the lower the density, with the maximum temperature (and lowest density) being at the melting/freezing point.
That depends on the liquid and the solid. Liquid mercury has a very high density. Liquid gasoline has a very low density. At the melting point the density of a liquid and a solid are almost the same.
It floats
float, depending on its density relative to the density of the liquid. If the solid is denser than the liquid, it will sink. If the solid is less dense than the liquid, it will float.
The fact that ice floats on water is evidence that its solid form is less dense than its liquid form at its freezing/melting point. This is due to the unique arrangement of water molecules in the solid state, where hydrogen bonds create a lattice structure that causes ice to be less dense.
Gasses have an incredibly low density, less than a liquid or a solid.
Whether the solid will float or sink in a solid-liquid mixture depends on the relative densities of the solid and the liquid. If the density of the solid is greater than that of the liquid, then the solid will sink. If the density of the solid is less than that of the liquid, then the solid will float.
Not always - the density of a liquid may be greater or less than that of the solid form depending on the molecular structure and arrangement. For example, water is an exception as its solid form (ice) is less dense than its liquid form.
Because the overall density of a can is less than the density of water, a solid aluminium pole has a density greater than water
it floats
Except at EXTREME pressures (like over 200 MPa), ice is less dense than liquid water. In the case of polar water this is even more the case since polar water has a fair amount of salt dissolved into it, raising it's density, while the ice is nearly pure water.
just because accept it ok!
To determine if a solid object is more dense or less dense than water, you compare their densities. The density of water is approximately 1 gram per cubic centimeter. If the solid object has a density greater than 1 g/cm^3, it is more dense than water and will sink. If its density is less than 1 g/cm^3, it is less dense than water and will float.