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Stales, If you come across the SG of ice, great. I'd be interested in reading here how ice compares to Evenkite.
In the spirit of rock solid scientific investigation,
WW
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Dear wwh: Thanks for Katahdin, not Qtadin!! I'm not qihddin'!
DubDub
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Dear WW: I was a boy long enough ago that my parents could let me stay out until 3AM on moonlit nights during Christmas holidays. There was a twenty acre pond that had been created by damming a large brook to cut ice for sale long before refrigerators were invented. There was a large island on which we were allowed to build huge bonfires. I still remember the sounds the ice made, expanding until suddenly huge cracks would form to releave the stress. The specific gravity of ice would be depend on the temperature of both the ice and the water, and so would not be useful. Let it go that it is less than one.
Think of what the world would be like if ice sank. The oceans would be solid except for a film on the surface in summer. Life as we know it might be impossible.
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Carpal Tunnel
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Crossthreading wildly: from Jackie's lovely subject-line, "Fire and Ice", to a brief poem of that title by Robert Frost: http://www.bartleby.com/155/2.html
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And the contraction Keiva mentioned of water just before it freezes is what slowly destroys mountains,and makes potholes in roads, by water getting into any crack and then expanding with great power, though for a short distance. Many primitive people quarried stone by laboriously drilling a line of holes, filling them with water, which when it froze would split off a large block.
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Bill:
Perhaps even more interesting is another characteristic of water. Most things, as they get colder, become smaller in size though of course retaining the same mass. A red-hot iron ring will contract around a wooden wheel to become so tight the spokes creak in protest.
Water is like this down to 4 degrees Centigrade. It's at that point that water is its densest. But as you cool the water further towards zero Centigrade, it actually expands in size! I cannot remember the chemistry/physics reason why this is so, but 'tis true. In fact, the gram was at one time defined as a cubic centimeter of water at the temperature of 4 Centigrade because that way everyone can determine exactly what a gram is.
Or should I have been saying Celcius?
TEd
TEd
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old hand
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dubdub
Found out all about ice.
The reference states that ice is one of the most common minerals on the planet. Interestingly however, it adds that there are no minerals with similar properties - it is unique.
Pure ice has an SG of 0.917 (well, I was close), a hardness of 1.5 (ie it will scratch talc), a vitreous lustre, no cleavage and its tenacity is rated as "brittle".
I'm now off to research SG's. As ice technically doesn't exist at standard temperatures and pressures, I'm wondering if STP is part of the definition after all.
google-eyed stales
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old hand
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The term specific gravity, symbolized sp gr, (what about SG?) refers to the ratio of the density of a solid or liquid to the density of water at 4 degrees Celsius. The term can also refer to the ratio of the density of a gas to the density of dry air at standard temperature and pressure, although this specification is less often used. Specific gravity is a dimensionless quantity; that is, it is not expressed in units.
I'm assuming that "at 4 degrees Celsius" refers only to the water in the equation???? Thus, one would calculate the density of ice at whatever temperature and pressure and then ratio it against the value for water to get the sp gr.
stales
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Thanks, Stales, for the research. I'm going to send this thread to a local geologist and see what his take is on it. Will post his response later in the week.
Best regards,
Dub
PS: that 4 degrees Celsius seems a bit unfair to ice. By the way, I really enjoyed your quick calculation a few posts back about your estimated SG of ice. Impressive!
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