Why the specific weight of water increases by heating from 0 to 4 degree centigrade?

Answer 1

The density of water decreases below 4°C because of the shape of water molecules and their electrical dipoles. The hydrogen atoms are located roughly 120° apart on the oxygen atom, and this results in a hexagonal crystalline lattice in ice. As it happens, the arrangement into the lattice starts below 4°C, at which point the cold water molecules are in their densest configuration.

Answer 2

'cuz as water is cooled from 4 to 0 degrees, the molecules arange themselves in hexagon shapes. This is why ice crystalizes and why snowflakes have six points. But since the molecules are organized into hexagons, which leaves a lot of empty space, a given number of molecules will take up more space at 0 degrees than 4 degees. It becomes less dense. That's why ice floats in water, and freezing water cracks roads (the ice expands in the cracks).

Answer 3

Density or in other words specific weight by definition is mass divided by volume.

If you realize that water consists of molecules and that those have to be arranged geometrically, it might be understandable, that their specific weight is variable. For example in vapor of water, the molecules are completely free to fly ... so their specific weight is low .... because volume is high for a given number of molecules. When you freeze them, they stick together in ice crystals .... so the same number of molecules need a smaller volume .... meaning this their specific weight is higher than in vapor.

The liquid state is also an arrangement of molecules. And since the arrangement of the molecules is depending on temperature, also specific weight does. Resulting from the dipole character of water, in the range of 0 to 4 degrees the specific weight increases, whereas from 4 to 100 and higher it decreases.

Answer 4

Water is at its densest at 4 degrees, it will weigh more per unit of mass at 4degrees than at 0 degrees.

Answer 5

do you know this?
P1.V1.T1=P2.V2.T2

P= Pressure
V=Volume
T=Temperature

If P and V are stable in both of situation then specific weight of water increases by heating
Don't forget, m=V.d and as long as m and V stable then it must be d (specific weight of water) sholud increase by heating

sorry for my english. I hope you will understand me

Answer 6

water at this temperature range has minimum volume. generally notice that water has a specific propeties that is different from other material . carbon is similair to water too.

Answer 7

It just does, there's no way to explain it simply.

Answer 8

pressure?