Re: Re: Water and watering etc.

dave evans (T442119@RUTADMIN.RUTGERS.EDU)
Wed, 28 Jun 95 17:14 EDT

> From: "Rupert G. Goldie" <rgg@AAII.OZ.AU>
>
> Yes, but don't forget that the energy required for H2O to change state
> from liquid to gas is far more than the energy required to heat the
> same amount of liquid from 0C to 100C (if I remember correctly - it's
> been quite a while).
>
If I remember correctly, 1 gram of frozen water take .5 calories
to raise the temp one degree centigrade. To melt 1 g. H2O, or
freeze it for that matter, takes about 80 cal. and it will still
be 0 C. Now liquid water is easy, add or take away 1 cal. from
1 g. and it's temp. will change by one degree C.. Infact that's
where the definition of the calorie comes from. Finally, to
vaporize 1g. water at 100 C. into steam at 100 C. takes something
like 216 cal. This is why steam can burn you so very fast.
I'm not sure of exact numbers here but they are fairly close.

Dave Evans