Talk:Water (data page)

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1 heat of evaporation
2 Notable safety precautions
3 Specific density
4 Water reheating
5 Data for real water?

[edit] heat of evaporation

I was looking for the heat of evaporation (i.e. turning water that is already at 100 degrees centigrade into steam of 100 degrees centigrade).

I can't find that data on this page, and it lacks explanation of the meaning of what it does present, so that it is unfortunately not usable by me.

Fortunately, searching wikipedia for 'specific heat capacity' and 'heat of evaporation' does provide the needed data. Specific heat 4.2 J/gram Kelvin Evaporation 2260 J/gram So evaporation equivalent to 538 Kelvin temperature increase.

I would like these data to be linked from 'water'. I hope this 'talk' page does that, but it would be better if these data were added to the main physical properties table (as they are for other substances).

See de:Wasser (Stoffdaten) for some tables which could be easily translated. --Saperaud 07:08, 9 October 2005 (UTC)

I am endeavoring to translate the material and post the result on water (data page). Karlhahn 17:13, 12 October 2006 (UTC)

[edit] Notable safety precautions

"The handling of this chemical may incur notable safety precautions. It is highly recommend that you seek the Material Safety Datasheet (MSDS) for this chemical from a reliable source such as SIRI, and follow its directions."

Umm... it's water. Need I say more?

Overdosing on water can create an electrolyte imbalance in your body and kill you. So don't drink too much water.

Why is this part even included? Is it to conform to some sort of stanards materials page? If not, I'd say remove it. It makes the whole thing look like a joke. --Alf 20:54, 24 July 2006 (UTC)

I agree that the safety precautions does not belong here. First, if you want jokes, go to a comedian nightclub, not wikipedia. Second, it's not data. If there are no objections, I'm going to take it out this weekend. Karlhahn 12:42, 6 October 2006 (UTC)

[edit] Specific density

I came to this page from the main water page looking for specific density. When I didn't find it here I googled it, and was embarrassed to find the answer (because it's such a gimme). Of course it's a no-brainer for many people, but for those of us having a Homer moment, or who haven't done anything with science since high school, wouldn't it be a good idea to include it? I am not familiar with the chemistry pages so I don't know where to add it. For an example of some of the data that could be added to the water data page, see Hydrochloric Acid.--Anchoress 14:55, 1 February 2006 (UTC)

Added densities at various temperatures to this page today. Karlhahn 19:35, 1 October 2006 (UTC)

It seems that this table has different values from the one at Water (molecule), Am I correct or have I overlooked something. I compared the values at 4 degrees Celsius, which here is said to be 1g/cm3 whereas in the other article it says 0.9999720 g/cm3.

Fixed table. Units should have been g/ml. Added conversion factor in table header. Density at 4°C now agrees with both CRC 44th ed., page 2190 and with Langes 10th ed, page 1199. Karl Hahn (T) (C) 11:49, 26 September 2007 (UTC)

Is that the "To convert to g/cm^3, multiply g/ml by 0.999973". This seems wrong. 1 litre = 1 dm^3 (Concise Science Dictionary 1988) so 1 cm^3 = 1 ml exactly. Different densities in different sources may be that before 1964 a litre was slightly larger, in fact 1 dm^3 was then 0.999972 l (Litre). The values in Water (molecule) is probably more right. /David A 85.231.140.117 —Preceding signed but undated comment was added at 21:56, 29 September 2007 (UTC)

Moreover, Wikipedia itself defines Litre as 1 dm^3, so this conversion factor should probable be dropped.--81.34.28.87 (talk) 18:09, 22 November 2007 (UTC)

The confusion with converting g/ml to g/cm³ arose due to obsolete usage of the definition of Liter (see History section), although the quoted source probably had the units right at that time. I converted the data to modern units. Xenonice (talk) 22:05, 26 November 2007 (UTC)

[edit] Water reheating

How many times can you reheating water in a kettle... is it safe to reheat especially when useing to feed new born babies− —The preceding unsigned comment was added by 82.45.231.180 (talk) 18:43, 7 February 2007 (UTC).

It probably depends on the quality of tap water and on what the kettle is made out of. Usually kettles accumulate deposits of weakly-soluble residues inside. Reheating can put more of that residue back into the water. Also, repeated reheating can dissolve some of the kettle material into the water. Both effects are probably harmless (as long as the kettle material doesn't contain toxic substances). Xenonice (talk) 22:05, 26 November 2007 (UTC)

[edit] Data for real water?

This data appears to all be for pure water only. The article should state this limitation clearly at the start. Having such chemical-theory data is a good start, but most of us are dealing with real water: tap water, rain water, lake water, sea water, etc. We want density etc data for real water. Until such is added, please add at least links to such data! -69.87.199.87 (talk) 10:20, 6 June 2008 (UTC)