Why isn't ice cold water ice?

Answer 1

state changes take energy too. even water ridiculously close to freezing would need to lose more energy than just the amount to cool it to 0 celcius because it needs to change from liquid to solid.

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Answer 2

The temperature at which water freezes is also the same as when it melts. Its unstable at that temp. If you go a fraction colder then it would turn to ice but because cold water with ice in it is absorbing heat from its surroundings the unstable temp stays above freezing.

Answer 3

First, let's quickly recap what a calorie is. A calorie is the amount of energy required to be deducted from a gram of water in order to cool it by 1 degree centrigrade.

So if a gram of water is kept at 1 degree centigrade, then 1 calorie of heat extracted from it will make the temperature of water drop down to 0 degrees centigrade, and become ice-cold. BUT it will still be water. Why?

Because to convert this gram of ice-cold water kept at 0 degree centigrade to ICE at 0 degree centigrade, we need to extract 80 calories of heat energy. This energy is called Latent Heat. That's a LOT of energy required.

Answer 4

Because the freezing point of water is 32 degrees F and the melting point of ice is 32 degrees F

Answer 5

in reality, there's no such thing as ice cold water, people are just exaggerating, because water cannot be as cold as ice since when water reaches a certain temperature (0-4 degree celsius), it starts to crystallize and turn to ice

Answer 6

Great question, technically it's not really ice cold it's as cold as it could go before turning into ice!

Answer 7

It is all to do with latent heat.

Let us consider melting ice (this requires adding some energy rahter than subtracting energy, allways easier to imagine).

Take a lump of ice that is below freesing point. To heat it up, we need to add energy, and we can calculate how much energy we need. The specific heat of a substance is a property that tells us how much energy we need to raise the temperature. The units of specific heat are "joules per gram per kelvin". A value of 1 would indicate that 1 joule of energy will raise the temperaturee of 1 gram of our material by 1 kelvin (that is 1 degree C). The specific heat of water ice is 2.114 and the specific heat of liquid water is 4.18.

Once we get our lump of ice up to freezing point ( 0 degrees C) we can go ahead and melt it. The water molecules in ice are not moving around too much, the same as in any solid. The molecules in water are, of course, moving around a lot more. To make the molecules more mobile we obviously need to add some energy. We can, in fact, add enough energy to melt the ice but not raise it's temperature. The energy required to do this is known as latent heat. In the case of the state change of solid to liquid or liquid to solid, we refer tot he latent heat of fusion. The latent heat of fusion has the units joules per gram. The latent heat of fusion of water is 335 which means that we need 335 joules of enrgy to convert 1 gram of ice at 0 degrees centigrade to 1 gram of water at 0 degrees centigrade.

To freeze our water, we need to remove the latent heat of fusion. The amount of energy that we need to remove is just the same as the amount that we previously needed to add.

A similar thing happens at boiling point except that we refer to the latent heat of vapourization.

You should be able to see from this that we can have water and ice existing in the same container and the temperature of both being 0 degrees C.

Answer 8

Because that is just a phrase, it is not really ICE COLD!

Answer 9

Because then it would not be water it would be ice!

Answer 10

It's not quite cold enough to make the "change of state" transition.