Naked Science Forum
Life Sciences => The Environment => Topic started by: neilep on 14/09/2008 22:50:31
-
Dearest Huggable Icebergologists !
As a sheepy I am of course naturally fascinated by icebergs,especially climbing them !
Look, here's one !
[ Invalid Attachment ]
Nice eh ?..being delivered Tuesday !
How come the salty sea water doesn't melt it ? !..or does it ?
............say it hanged around the arctic for a good long time and didn't travel to warmer climes...would it not melt at all ?..after all the sea water hasn't frozen so I'm guessing it does melt !...is there a formula to determine how much of it melts a day ?
..and if not..why the hell not ? *sheepy slams table*
thanking ewe for your iceberg orientated melting answers !
Your Sincerely
neil
Icecohen...I mean Iceberg asker ! Oy vay !!
xxxxxxxxxxxxxxxxxxx
-
LOL.. Thats a good question.. one would think it would eventually start melting...salt water I would assume would naturally help that especially if with the amounts involved.. Surely there will be some expert ice cap person to come along and give you the proper answer about the details surely someone has done this formula investigation before!
-
Icebergs are made of fresh (pure) water, (cf. sea-ice which is made of saltwater).
The freezing point of pure water is 0 oC,
The freezing point of seawater is -2 oC, (i.e. seawater remains liquid down to -2 oC).
So freshwater ice would not melt if in seawater at 0 oC or lower.
[Although the sun could melt some of the iceberg exposed above the water].
-
LOL.. Thats a good question.. one would think it would eventually start melting...salt water I would assume would naturally help that especially if with the amounts involved.. Surely there will be some expert ice cap person to come along and give you the proper answer about the details surely someone has done this formula investigation before!
As a firm believer in empirical study I have conducted my own experiment . I have kept an ice cube floating in some salt water in a cold place. It melted !...I don't get it !!..I just don't get it !!
-
Icebergs are made of fresh (pure) water, (cf. sea-ice which is made of saltwater).
The freezing point of pure water is 0 oC,
The freezing point of seawater is -2 oC, (i.e. seawater remains liquid down to -2 oC).
So freshwater ice would not melt if in seawater at 0 oC or lower.
[Although the sun could melt some of the iceberg exposed above the water].
Thanks for this RD
I'm still a tad confused cos although the sea water as ewe say freezes at -2c won't the salt within it still melt the iceberg at the very point of contact ?
*sheepy ponders...ti's hard ewe know?*
Yep...ewe're right !!
THANKS
-
LOL.. Thats a good question.. one would think it would eventually start melting...salt water I would assume would naturally help that especially if with the amounts involved.. Surely there will be some expert ice cap person to come along and give you the proper answer about the details surely someone has done this formula investigation before!
As a firm believer in empirical study I have conducted my own experiment . I have kept an ice cube floating in some salt water in a cold place. It melted !...I don't get it !!..I just don't get it !!
Maybe you needed more salt!
-
When most anhydrous (dry) salts are dissolved in water there is an exothermic reaction (releasing heat), a.k.a. "heat of hydration" ...
One of the most common types of heat of solution is that for the dissolution of a substance, most commonly salts, in water...
The enthalpy of solution for aqueous solutions is called the enthalpy of hydration or, simply the heat of hydration...
The heat of solution for formation of aqueous solutions of most salts is positive [exothermic].
http://www.bookrags.com/research/heat-of-solution-woc/
This heat (of hydration) could melt ice, but this release of heat would not occur with salt water: the salt in the seawater is already dissolved (hydrated).
Re: your ice cube experiment, was the temperature of salt water at 0 oC, or preferably lower, say -1 oC ?.
PS
To create artificial seawater you'll need to add about 35 grams of table salt to one litre of water.
-
Could a reason be that salty water is denser than fresh water in it's molecules for defrosting although the ice shelves are disappearing all too soon.
Global warming, greenhouse gases etc.