Is cold water heavier than hot water?

Answer 1

The density of hot water is less than cold water.
Density being the mass or weight per unit volume.

at 1C p=0.9901 g/cm^3
at 90C p=0.9653 g/cm^3

But one has to be carefully since the relationship between density and temperature is not always linear (see ref. below)

Answer 2

For the same amount of volume, yes of course. Put a liter of cold water into a beaker. Heat it and watch as the water rises in the beaker as it gets warmer. Pour off enough of the hot water to get back to the same level. It has to weigh less than the cold water you started with. Cold water weighs more than hot water of the same volume.

Answer 3

Wow!
The answers I have read are all over the place.
Anything that is denser will weigh more per amount of volume. Cold water is denser than hot water. A liter of cold water will weigh more than a liter of hot water. The hot water is moving faster and will fill up more space than the cooler water without adding any mass.

Answer 4

Mr. Wizard did this experiment. When the hot water dyed red was on top, it stayed, and when the cold water dyed blue was on top, the two switched. Funny how the water didn't turn purple, but Mr. Wizard....was he just Captain Picard in disguise? Do you even remember him, or are you of the Bill Nye the Science Guy generation/

Answer 5

I take it you are asking "is a fixed volume(say exactly one litre)
of cold water heavier than exactly one litre of hot water?
The anwer is yes,the molecules in hot water move more quickly than those in cold water,as a result they elbow themselves more space.
A more usual way of asking this question is"IS COLD WATER MORE DENSE THAN HOT WATER".Again the answer is yes.

Answer 6

For the same volume of water, the hot water will be less dense due to expansion and will be a little lighter.

Answer 7

Nope, when the hot water becomes steam, then cold water is heavier.

Answer 8

i think the weight of both cold water and hot water is same .it is only the density variation..............so when a vessel of water is heated hot water at base being less dense rises up and cold water goes down.it is the volume that differs

Answer 9

Not heavier, but it is more dense. Water's density peaks around 4 degrees Celsius.

Answer 10

Erm....I'm not going to pretend I actually know the answer to this, cos I don't BUT it seems to me that hot water will start to emit steam, becoming lighter all the time, so probably the answer is yes.