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Can one do a DNA test from vomit? —Preceding unsigned comment added by 12.216.168.198 ( talk) 00:21, 14 April 2009 (UTC)
is there a name for a star that is named as being a member of one constellation, but actually exists inside the boundaries of another? does such a thing even exist? i had a dream that a star like that was called a "tapuo" or something, so now i'm curious if it actually exists. 99.245.16.164 ( talk) 00:35, 14 April 2009 (UTC)
Diamonds have some properties of ionic compunds (they are hard, have high melting and boiling points and can conduct electricity) but other properties (such as diamonds not being able to dissolve in water and not being brittle) are not properties of ionic compounds. —Preceding unsigned comment added by 174.6.144.211 ( talk) 01:52, 14 April 2009 (UTC)
But if diamonds are covalent compoounds then why are they hard, have high melting and boiling points are able to conduct electricity? —Preceding unsigned comment added by 174.6.144.211 ( talk) 02:18, 14 April 2009 (UTC)
More generally, lots of things you learn in school are general guidelines or observed trends, not the actual reasons. "Ionic has property X, non-ionic has property not-X" is only true if being ionic is the exact and only cause of property X. But that's not true for this case: the actual cause of "high-melting" isn't "ionic", but rather it's related to how the molecules are held together. Ionic molecules are merely a common type that are held together in a way to give high-mp. For that reason, "ionic gives high mp" doesn't mean you can say "therefore non-ionic will not be high mp": being ionic is not the only type of molecule that is held together in this certain way. Same goes for any property and any characteristic: need to see how/why the trend works, not use the observed trend as the actual cause and black'n'white separation (correlation vs causation). DMacks ( talk) 14:18, 14 April 2009 (UTC)
Atropine is historically used as an anaesthetic, and apparently is used as a premedication for general anaesthesia today, I can see why you would want to have a lower heart rate, bronchodilation and the like, but as atropine is a CNS stimulant, my question is, why would you use it as an pre-anaesthesia. I know hyoscine would be a better choice. MedicRoo ( talk) 11:14, 14 April 2009 (UTC)
The main reasons for using anticholinergic drugs as pre-medication are:-
Other possible benefits are relatively unimportant. The sedative effect of hyoscine is not usually regarded as beneficial when giving general anaesthesia. Indeed the sedative effect of hyoscine may be tricky to predict, especially in the elderly. Other anaesthetic drugs give a more reliable response. Axl ¤ [Talk] 17:34, 14 April 2009 (UTC)
The hydrogen Peroxide(H2O2) you buy at pharmacies are so low concentrated and are dissolved in water(H2O), and I want more pure hydrogen Peroxide, but don't want to use so much money to buy the expensive high concentration hydrogen Peroxide(H2O2) from large companies.Can I remove the water by evaporation(H2O2's boiling point is 150.2 °C but water's boiling point is 100 °C)? Please tell me other methods too!
The Successor of Physics
15:19, 14 April 2009 (UTC)
H2O2 has a density about 40% greater then water, perhaps a centrifuge could separate them? 65.121.141.34 ( talk) 15:39, 15 April 2009 (UTC)
http://www.math.union.edu/~dpvc/math/4D/projections/welcome.html
According to this link, what would we look like to a entity that can see in 4D? -- Reticuli88 ( talk) 15:36, 14 April 2009 (UTC)
Ok. What would we look like as a 4D entity? -- Reticuli88 ( talk) 18:45, 14 April 2009 (UTC)
The reason I brought this up was because of the link below:
The author describes what a 4D entity would appear to us: "....resemble flesh-colored balloons constantly changing in size." Also, as scene in the movie Contact, Jodie Foster's character experiences a sort of 4D experience, I think. I mean the scene when she exclaims "They're alive!" the first time; the scene where it appears she splits in two. Does anyone know this reference? I'm just trying to get some handle what 4D would appear to us lowly humans. -- Reticuli88 ( talk) 20:40, 14 April 2009 (UTC)
In this 4D world our 3D world would appear like the stiff flat cross section showing at 1:48 to 2:04. Cuddlyable3 ( talk) 00:08, 17 April 2009 (UTC)
A friend of mine told me that you can see the constellation Orion in Australia, but that it looks upsidedown then what is normal in the northern hemisphere. Was he just joking with me, or is there truth to this? 65.121.141.34 ( talk) 16:12, 14 April 2009 (UTC)
Note that it's not as simple as "right-side-up or upside-down". Even at the same location, the same constellation will be seen in different orientations at different times of day when it is in different parts of the sky. Similarly, it is not true that "down" is exactly the opposite direction for people in different hemispheres unless they happen to be in antipodal locations. I'm in Toronto; compared to someone in Buenos Aires I'm not upside-down, I'm sideways.
For a simple example that doesn't require you to wait for nightfall, look at the moon at different times on the same day. The center of the lighted side always points toward the sun -- therefore it points above the horizon when the sun is up, but below the horizon when the sun is down. But the same features on the moon's face are visible, so you can see it's a different way up with respect to you. Well, for someone in a different part of the Earth it's different again. --Anonymous, expanded 04:55 UTC, April 15, 2009.
What is the cause of muscle pain associated with the flu or other infections? I looked at myalgia - no help there. - 71.239.110.144 ( talk) 18:38, 14 April 2009 (UTC)
Hello.
A stock solution of HCl(aq) has a density of 1.19 g/mL and a percentage purity of 39.1%. A lab requires 7.25 L of 0.500 mol/L solution. What volume of stock solution do I need before dilution?
I divided the amount of hydrochloric acid needed (3.625 mol) by [HCl(aq)39.1% (12.76165661 mol/L), reaching the conclusion of 284 mL. The answer key says 303 mL. This is not homework counting for marks. Otherwise, my teacher would not have given me the answers. Did I do something wrong? Thanks in advance. -- Mayfare ( talk) 20:58, 14 April 2009 (UTC)
can stones get fire as wood (at any temprature)i.e as wood cause to increase fire ,can stones do same thing —Preceding unsigned comment added by True path finder ( talk • contribs) 22:01, 14 April 2009 (UTC)
what r the permanet, bad r good effects of Muslim Fasting (which means without water and any otherthing else for average 12 houres ) —Preceding unsigned comment added by True path finder ( talk • contribs) 22:06, 14 April 2009 (UTC)
How would someone be able to eat their whole own self? Since eating one's whole self requires eating their mouth, how would they be able to eat afterwards? And since it requires eating their digestive system, how would they be digested? 58.165.25.29 ( talk) 23:26, 14 April 2009 (UTC)
In the neighbourhood where I live, all of the houses share a single mail pick-up point - it's like an apartment complex - there are no mailboxes outside each house. Instead, over by the park, there are rows of tiny locked mailboxes - one for each house - for which you have a key. There is also a row of much larger mailboxes for packages and such. When you get a large parcel, the mailman puts it into one of the large boxes, locks it and places the key into your individual mailbox. Now - here's the thing. The large mailboxes are set up so that you put the key into the lock - turn it to get your package out - but the key won't turn back again - and it won't come out of the keyhole so nobody can steal it. There is a second keyhole that the postman puts a special key into that releases the first key.
I've been trying to figure out how this fiendish mechanism works - the mailbox key looks like a perfectly ordinary key. It's obviously a ratchet or something - but curiosity demands that I know how it ACTUALLY works. Does anyone know of a diagram or something?
SteveBaker ( talk) 23:46, 14 April 2009 (UTC)
Science desk | ||
---|---|---|
< April 13 | << Mar | April | May >> | April 15 > |
Welcome to the Wikipedia Science Reference Desk Archives |
---|
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages. |
Can one do a DNA test from vomit? —Preceding unsigned comment added by 12.216.168.198 ( talk) 00:21, 14 April 2009 (UTC)
is there a name for a star that is named as being a member of one constellation, but actually exists inside the boundaries of another? does such a thing even exist? i had a dream that a star like that was called a "tapuo" or something, so now i'm curious if it actually exists. 99.245.16.164 ( talk) 00:35, 14 April 2009 (UTC)
Diamonds have some properties of ionic compunds (they are hard, have high melting and boiling points and can conduct electricity) but other properties (such as diamonds not being able to dissolve in water and not being brittle) are not properties of ionic compounds. —Preceding unsigned comment added by 174.6.144.211 ( talk) 01:52, 14 April 2009 (UTC)
But if diamonds are covalent compoounds then why are they hard, have high melting and boiling points are able to conduct electricity? —Preceding unsigned comment added by 174.6.144.211 ( talk) 02:18, 14 April 2009 (UTC)
More generally, lots of things you learn in school are general guidelines or observed trends, not the actual reasons. "Ionic has property X, non-ionic has property not-X" is only true if being ionic is the exact and only cause of property X. But that's not true for this case: the actual cause of "high-melting" isn't "ionic", but rather it's related to how the molecules are held together. Ionic molecules are merely a common type that are held together in a way to give high-mp. For that reason, "ionic gives high mp" doesn't mean you can say "therefore non-ionic will not be high mp": being ionic is not the only type of molecule that is held together in this certain way. Same goes for any property and any characteristic: need to see how/why the trend works, not use the observed trend as the actual cause and black'n'white separation (correlation vs causation). DMacks ( talk) 14:18, 14 April 2009 (UTC)
Atropine is historically used as an anaesthetic, and apparently is used as a premedication for general anaesthesia today, I can see why you would want to have a lower heart rate, bronchodilation and the like, but as atropine is a CNS stimulant, my question is, why would you use it as an pre-anaesthesia. I know hyoscine would be a better choice. MedicRoo ( talk) 11:14, 14 April 2009 (UTC)
The main reasons for using anticholinergic drugs as pre-medication are:-
Other possible benefits are relatively unimportant. The sedative effect of hyoscine is not usually regarded as beneficial when giving general anaesthesia. Indeed the sedative effect of hyoscine may be tricky to predict, especially in the elderly. Other anaesthetic drugs give a more reliable response. Axl ¤ [Talk] 17:34, 14 April 2009 (UTC)
The hydrogen Peroxide(H2O2) you buy at pharmacies are so low concentrated and are dissolved in water(H2O), and I want more pure hydrogen Peroxide, but don't want to use so much money to buy the expensive high concentration hydrogen Peroxide(H2O2) from large companies.Can I remove the water by evaporation(H2O2's boiling point is 150.2 °C but water's boiling point is 100 °C)? Please tell me other methods too!
The Successor of Physics
15:19, 14 April 2009 (UTC)
H2O2 has a density about 40% greater then water, perhaps a centrifuge could separate them? 65.121.141.34 ( talk) 15:39, 15 April 2009 (UTC)
http://www.math.union.edu/~dpvc/math/4D/projections/welcome.html
According to this link, what would we look like to a entity that can see in 4D? -- Reticuli88 ( talk) 15:36, 14 April 2009 (UTC)
Ok. What would we look like as a 4D entity? -- Reticuli88 ( talk) 18:45, 14 April 2009 (UTC)
The reason I brought this up was because of the link below:
The author describes what a 4D entity would appear to us: "....resemble flesh-colored balloons constantly changing in size." Also, as scene in the movie Contact, Jodie Foster's character experiences a sort of 4D experience, I think. I mean the scene when she exclaims "They're alive!" the first time; the scene where it appears she splits in two. Does anyone know this reference? I'm just trying to get some handle what 4D would appear to us lowly humans. -- Reticuli88 ( talk) 20:40, 14 April 2009 (UTC)
In this 4D world our 3D world would appear like the stiff flat cross section showing at 1:48 to 2:04. Cuddlyable3 ( talk) 00:08, 17 April 2009 (UTC)
A friend of mine told me that you can see the constellation Orion in Australia, but that it looks upsidedown then what is normal in the northern hemisphere. Was he just joking with me, or is there truth to this? 65.121.141.34 ( talk) 16:12, 14 April 2009 (UTC)
Note that it's not as simple as "right-side-up or upside-down". Even at the same location, the same constellation will be seen in different orientations at different times of day when it is in different parts of the sky. Similarly, it is not true that "down" is exactly the opposite direction for people in different hemispheres unless they happen to be in antipodal locations. I'm in Toronto; compared to someone in Buenos Aires I'm not upside-down, I'm sideways.
For a simple example that doesn't require you to wait for nightfall, look at the moon at different times on the same day. The center of the lighted side always points toward the sun -- therefore it points above the horizon when the sun is up, but below the horizon when the sun is down. But the same features on the moon's face are visible, so you can see it's a different way up with respect to you. Well, for someone in a different part of the Earth it's different again. --Anonymous, expanded 04:55 UTC, April 15, 2009.
What is the cause of muscle pain associated with the flu or other infections? I looked at myalgia - no help there. - 71.239.110.144 ( talk) 18:38, 14 April 2009 (UTC)
Hello.
A stock solution of HCl(aq) has a density of 1.19 g/mL and a percentage purity of 39.1%. A lab requires 7.25 L of 0.500 mol/L solution. What volume of stock solution do I need before dilution?
I divided the amount of hydrochloric acid needed (3.625 mol) by [HCl(aq)39.1% (12.76165661 mol/L), reaching the conclusion of 284 mL. The answer key says 303 mL. This is not homework counting for marks. Otherwise, my teacher would not have given me the answers. Did I do something wrong? Thanks in advance. -- Mayfare ( talk) 20:58, 14 April 2009 (UTC)
can stones get fire as wood (at any temprature)i.e as wood cause to increase fire ,can stones do same thing —Preceding unsigned comment added by True path finder ( talk • contribs) 22:01, 14 April 2009 (UTC)
what r the permanet, bad r good effects of Muslim Fasting (which means without water and any otherthing else for average 12 houres ) —Preceding unsigned comment added by True path finder ( talk • contribs) 22:06, 14 April 2009 (UTC)
How would someone be able to eat their whole own self? Since eating one's whole self requires eating their mouth, how would they be able to eat afterwards? And since it requires eating their digestive system, how would they be digested? 58.165.25.29 ( talk) 23:26, 14 April 2009 (UTC)
In the neighbourhood where I live, all of the houses share a single mail pick-up point - it's like an apartment complex - there are no mailboxes outside each house. Instead, over by the park, there are rows of tiny locked mailboxes - one for each house - for which you have a key. There is also a row of much larger mailboxes for packages and such. When you get a large parcel, the mailman puts it into one of the large boxes, locks it and places the key into your individual mailbox. Now - here's the thing. The large mailboxes are set up so that you put the key into the lock - turn it to get your package out - but the key won't turn back again - and it won't come out of the keyhole so nobody can steal it. There is a second keyhole that the postman puts a special key into that releases the first key.
I've been trying to figure out how this fiendish mechanism works - the mailbox key looks like a perfectly ordinary key. It's obviously a ratchet or something - but curiosity demands that I know how it ACTUALLY works. Does anyone know of a diagram or something?
SteveBaker ( talk) 23:46, 14 April 2009 (UTC)