Is water more dense when cold?

Answer 1

Water has this exceptional property..
Listen to this...
As the temp. is lowered the density increases...
till 4 degree Celcius...
Below which it starts decreasing again..
That means it is most dense at 4 degree Celcius...

Answer 2

Density rho = M/m^3 where M is mass and m^3 is the volume of that mass; weight = W = Mg; so W = rho m^3 g by substituting M = rho m^3 into the weight equation.

When an ice cube floats in a glass of water, the force of buoyancy from the water (W(w)) equals the weight (W(c)) of the ice cube; otherwise the cube would rise all the way out to the surface or sink all the way to the bottom of the glass.

Clearly the volume of water displaced by the cube is less than the volume of the cube (because some of the cube is still in the air above the water). In math talk, we can assert that m(w)^3 < m(c)^3 because some of the ice cube is out of the water it is floating in.

Because W(c) - W(w) = 0 when the ice cube is floating (there is no net force on the cube to accelerate it), we can write W(c) = rho(c) m(c)^3 g = W(w) = rho(w) m(w)^3 g and rho(c) = (m(w)^3/m(c)^3) rho(w)

AHA! Because (m(w)^3/m(c)^3) < 1.0 it is clear that rho(c) < rho(w); that is, the density of the ice cube (cold water) is less than the density of the liquid (warmer water).

Bottom line, the answer to your question is: it depends. Clearly cold water is not always denser than warmer water. Also, just because something is harder than something else, that does not necessarily mean it's denser than that something else.

Answer 3

Yes upto 4 degree C. density of water increases as it gets cooler.

Answer 4

obviously....
but not from 4-0 and 0-4 degree cebtigrade.