Subject: Can someone please explain?
Posted by: Mixamatosis
Date: Jan 21 17
I've read that it's dangerous to mix ammonia and bleach. Variously I've read that it can produce deadly cyanide gas, chlorine gas (which is said to be bad for you) and even explosions.
However swimming pools are kept fit for use with chlorine, and our urine contains ammonia but then we may clean toilets with bleach. Also many cleaning products contain either ammonia or bleach and it would be easy to use them unthinkingly in combination.
How is it that people aren't generally harmed by these dangers when swimming in swimming pools or doing daily cleaning, or are we being harmed at low level and is the harm cumulative?
Posted by: Mixamatosis
Date: Jan 21 17
I've read that it's dangerous to mix ammonia and bleach. Variously I've read that it can produce deadly cyanide gas, chlorine gas (which is said to be bad for you) and even explosions.
However swimming pools are kept fit for use with chlorine, and our urine contains ammonia but then we may clean toilets with bleach. Also many cleaning products contain either ammonia or bleach and it would be easy to use them unthinkingly in combination.
How is it that people aren't generally harmed by these dangers when swimming in swimming pools or doing daily cleaning, or are we being harmed at low level and is the harm cumulative?
526 replies. On page 18 of 27 pages. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
brm50diboll 
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Anyone can get in on a discussion, but they may want to actually bring up a topic: since no one has, I will return to my default: I had been discussing the Saturnian system. Saturn's largest moon, Titan, is the only moon outside of Earth's to have been landed on by a space probe, which Huygens did over ten years ago. Titan is also the only moon with a substantial atmosphere. Titan's atmosphere is overwhelmingly made of nitrogen. Earth's atmosphere is also largely nitrogen, but contains a significant amount of oxygen, which Titan's atmosphere does not. But the biggest difference is the temperature: Titan is vastly colder than Earth, so despite containing large amounts of organic material, including lakes of liquid methane, it is not considered a very promising place for life to exist. Reply #341. Jul 29 18, 2:11 AM |
LoveAnimals555
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Ummm.... I have one. Basically I have been stuck to physics now a days. First of all Brian would you like to have some words on Interference and Diffraction before I start with questions? Reply #342. Jul 29 18, 2:29 AM |
Mixamatosis
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LoveAniamls. No one need ask permission to comment on anything - just plunge right in. Brian - lakes of methane on Titan. Amazing. Methane and oxygen is explosive I understand where methane is around in significant quantity so that would be a difficult place to visit, however well insulated. You would have to be absolutely sure no oxygen could leak. Reply #343. Jul 29 18, 3:55 AM |
| Mixamatosis
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Sorry about my typo LoveAnimals Reply #344. Jul 29 18, 3:56 AM |
| LoveAnimals555
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Actually I am requesting Brian to say something on Interference and Diffraction. Reply #345. Jul 29 18, 5:33 AM |
| brm50diboll
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Very nice. Interference and Diffraction are two fundamental wave properties. All waves share these wave properties (which also include reflection and refraction), but these properties are often examined in the physics subdomain of optics, which is the study of light. Light, because of its quantum nature, has both particle and wave properties, a fact confusing to many who do not understand quantum mechanics and which caused a debate to rage over two hundred years as to whether light was a particle or a wave. Without revisiting the history of physics, light is both, and while this conclusion is definitely counterintuitive, so is quantum mechanics, and models have to be recognized for their inherent limitations when applied to real world phenomena like light. So diffraction occurs when light (or any wave) appears to "bend" as it passes through a narrow opening or around a corner. The effect is most obvious when the opening the light passes through is comparable in size to the wavelength of the light. Since light has a very small wavelength (400-700 nanometers), diffraction effects are typically not seen with light unless the opening the light passes through is less than one millimeter. These effects are best seen when projected onto a screen, typically one meter or so away from the slit where the light passes through. Then the diffraction of light produces bright and dark bands on the screen. Since diffraction depends on wavelength, and since there are multiple wavelengths in white light, the diffraction effect is clearest when monochromatic light (only one wavelength - or color) is used rather than for white light, where the effect is somewhat distorted by interference between the different wavelengths of light. Interference (just mentioned) is another wave phenomenon. It occurs when two different waves meet each other, either because they are originating from two different sources or because they have different wavelengths. The principle of superposition states that if two crests meet, the interference is *constructive* (or additive), but if a crest meets a trough, the interference is *destructive* (subtractive). Like diffraction patterns, interference patterns can be created by light projected onto a screen. The difference between a different one pattern and an interference pattern is that a diffraction pattern uses one narrow slit, whereas an interference pattern uses two closely spaced narrow slits. Both produce a pattern of alternating light and dark bands on the screen, which to a novice may look the same, but the underlying mathematics of the patterns are different and tell different things about the light. Since these boards do not allow pictures, I've explained the difference between diffraction and interference about as well as possible in words alone, but for someone really interested in seeing the difference, they should Google diffraction and Google interference and look at the pictures with the articles that come up. Reply #346. Jul 29 18, 2:16 PM |
| brm50diboll
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Newsflash: If you have ever wanted to see the planet Mars, now (the next few days) is the time to do it. Go out after sunset (an hour or so after, when twilight fades) and look to the East. You should see what appears to be a very bright reddish "star" slowly rising. This is Mars, which is unusually close to us now. The technical astronomical term is "opposition". Obviously, you need a clear night, but I just went out and looked at Mars. Very impressive. Reply #347. Aug 01 18, 8:28 PM |
| brm50diboll
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If Mark (terraorca) happens to see this, yes, Mars was reasonably close to the Moon the last few nights. Not so much now, because the Moon moves relatively fast in the sky. Mars' current position makes it visible over most of the world at night (except in the Arctic). The further north one happens to be, the further south Mars appears in the sky. From Texas, Mars rises in the East Southeast shortly after sunset. I said East, but it is a little south of East. From Ohio, it would appear even more south of due East than from Texas. Of course, if you were in New Zealand, Mars would appear to rise a little north of East. But it is pretty easy to spot an hour or so after local sunset almost anywhere except the far north. Look easterly, low in the sky to find it. As the night goes on, it will rise higher in the sky and track more towards the South. At midnight local time, except in the Southern hemisphere, Mars will be in the southern part of the sky. It then moves west and sets (but you won't see that, since it will set after the sun rises.) Reply #348. Aug 01 18, 9:20 PM |
| Mixamatosis
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I will try to see Mars but alas there are so many buildings blocking the view of 'low in the sky' I'm not sure if it will be possible. Reply #349. Aug 01 18, 11:37 PM |
| brm50diboll
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From England, Mars should be visible but very low in the sky. You need a clear night, obviously, but you need to be in a place with a clear view of the southeast. Buildings or trees can definitely interfere. To use a technical term, from England, the "altitude" of Mars will be less than 10° above the horizon. Reply #350. Aug 01 18, 11:47 PM |
| Mixamatosis
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Thanks Brian. I don't think I've got any chance. The horizon's not really visible round here. Too built up but I'll try. Our house faces north west one way and south east the other so that's helpful at least. As for clear skies in a city.... Reply #351. Aug 02 18, 2:36 AM |
| brm50diboll
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Thank God I'm a Country Boy - John Denver I can actually see stars and planets. It's nice. Even "city slickers" would be impressed to head out into the country and look up into the sky when it's clear and dark somewhere. Mars is quite cool right now. It rises in the east (more or less) after sunset and appears as a very bright reddish "star". But it is fairly low in the sky for most Northern Hemisphere observers. Now, from the Outback of Australia, Mars would appear almost directly overhead at local midnight. London, unfortunately, is pretty far north, has massive light pollution, and not a lot of clear skies, anyway. But I'll bet if I were in London, I would still see it, because I am very persistent and am good at spotting low sky objects in less than ideal conditions. I can see Canopus from Texas in February, a star that is usually seen only in the southern hemisphere. From where I am, Canopus (the second-brightest night star after Sirius) never gets more than 5° above the horizon. Reply #352. Aug 02 18, 3:09 AM |
| brm50diboll
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One more point: Planets pass from one zodiac constellation to another. At present, Mars is in Capricornus, near the Sagittarius border. But Capricornus is a very dim constellation, so even viewed from rural Texas, you see bright Mars and not much else nearby. The Sun passes through Capricornus (note that I am intentionally referring to it as Capricornus, *not* Capricorn, because Capricornus is the correct astronomical name for the *constellation*, whereas Capricorn is an astrological sign, which is not quite the same thing as a constellation) in January. What this means is that Mars is now at night where the Sun will be in January during the day, which is low in the sky for Northern Hemisphere observers, as Capricornus is a southerly zodiac constellation. Reply #353. Aug 02 18, 3:41 AM |
| brm50diboll
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Of the various smaller moons of Saturn, two that interest me are Enceladus, which has active geysers and is coated with water ice, and Mimas, which looks like the Death Star from Star Wars because of its single large crater (it has many craters, but this one is far larger than all the others) called Herschel. Reply #354. Aug 18 18, 11:22 PM |
| brm50diboll
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The planet Uranus (properly pronounced "your-uh-nus") is the first planet not known to the ancients that was discovered in modern times, by Sir William Herschel of England in 1786. Oddly enough, Uranus has a magnitude less than +6.0, which means it *can* be seen by the naked eye. But conditions have to be just right for this, and I'll admit I've never seen it with the naked eye, but I have spotted it pretty easily with binoculars. The only space probe to visit Uranus was Voyager 2, in 1986. It takes 84 years to make one orbit around the sun. Because of its extreme axial tilt (98°), Uranus keeps one pole pointed almost directly at the sun for several years, something no other planet does. The fact that Uranus's center of gravity and its center of magnetism are significantly off from each other, along with its bizarre axial tilt, suggests that some large object struck Uranus when it was forming to create its strange asymmetries. The blue-green color of its atmosphere is due to the presence of methane in significant amounts, although the atmosphere is mostly hydrogen and helium, like Jupiter and Saturn. Reply #355. Sep 03 18, 7:23 PM |
| Mixamatosis
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Imagine taking 84 years to orbit the sun if you had to endure a globally warmed Summer for 21 of them. Oooh uncomfortable. I dare say Uranus itself is too hostile an environment to live on. Too cold and not the right gases for breathing. I find it a bit strange that sometimes people ask you a question, or to provide information on a subject, and then never acknowledge your response or say thank you. Reply #356. Sep 04 18, 11:13 PM |
| brm50diboll
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Doesn't really bother me. Uranus, as a Jovian planet, can't really support life as we know it for a couple of reasons, especially: it has no solid surface, or even a liquid one. Like Jupiter, Saturn, and Neptune, it is made of gas that gets thicker and hotter as one gets deeper into it. Eventually, anything that falls into Uranus will get crushed by the massive pressure and scorched by the deep internal heat. And the second reason: in the outer layers, where the pressure may be tolerable, it is bitterly cold. Most astronomers looking for the possibility of life in our solar system do not consider any of the Jovian planets themselves, although certain of their moons are intringuing. The fact that Uranus has such extreme axial tilt means that it should have wide hemispheric temperature variations in different times in its 84-year long "year", but without a solid surface, it will not have "seasons" as we know them. Instead, dramatic changes in its atmospheric wind patterns should occur. Reply #357. Sep 05 18, 8:52 PM |
| LoveAnimals555
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Hey Brian, do you know what is Epidermal Turnover Time? If you have any idea about it then please explain it to me! Reply #358. Sep 06 18, 11:55 AM |
| brm50diboll
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Not totally sure. The epidermis consists of dead cells which flake off and are replaced by new dead cells from the basal layer of the epidermis (the only part of the epidermis which is alive and reproduces.) The time for newly formed epidermal cells to be pushed to the surface where they flake off is the turnover time, maybe 10-11 days, normally. Certain skin diseases like psoriasis reduce that turnover time, causing lesions to appear. But I haven't researched this recently and I am not a dermatologist. Reply #359. Sep 06 18, 7:25 PM |
| LoveAnimals555
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Actually I am confused as they taught us today in college that Epidermal turnover time is 52-75 days and it is different from shed off of keratinized cells of Stratum Corneum layer of epidermis. And further he (lecturer) said, that he will discuss about it in further classes and I found no time to ask what it is. Huh.. Got confused when I searched it on net. Reply #360. Sep 06 18, 8:45 PM |
526 replies. On page 18 of 27 pages. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
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