What physically causes gas pressure and how can you increase the pressure of gas?
Q. Also, I have a few other questions that I would like answered too :) Thanks for all your help. 1. How do temperatures in Celsius and Kelvin differ in their relationship with pressure? 2. How do you write an equation to express the relationship between pressure and temperature (K). Use symbols P, T, and c. 3. What should happen to the pressure of gas if Kelvin is doubled? 4. What shoul be the pressure at "absolute zero" Thanks!
Asked by Jenn - Wed Jan 16 13:06:57 2008 - - 1 Answers - 0 Comments

A. the gas law you can use is P1 * V1 = P2 * V2 T1 T2 (that's divided by) you can increase gas pressure by reducing the volume which the gas occupies (P1 *V1 = P2 * V2 of the same gas) while the temperature remains the same and also by reducing the temperature, while the volume remains the same this temperature (T1 and T2) is ALWAYS measured in Kelvins, so if you were to use degrees C, you have to add 273 to the figure to make it into Kelvins. I hope that answers no 2 if the temperature is doubled then it follows that the Pressure will also double (if the volume is kept the same) so that the equation written previously to be proven. i hope that helps!
Answered by oneworld - Thu Jan 17 05:35:56 2008

What would happen to the gas pressure inside the cylinder?
Q. Assume that you have a cylinder with a movable piston. What would happen to the gas pressure inside the cylinder if you decrease the volume of the gas to one third of the original volume? (a) The pressure would decrease by one third as well. (b) The pressure would be unchanged (c) The final pressure would be three times of the initial pressure. (d) The final pressure would be nine times of the initial pressure.
Asked by kkamazk - Sun Oct 25 08:50:19 2009 - - 4 Answers - 0 Comments

A. You have a confined gas in a cylinder with a movable piston. The gas will follow the combined gas law: P1V1/T1 = P2V2/T2. Since there is no mention of changes in T, we will assume that T remains constant. Then the gas follows Boyle's law. Solve for the new pressure, P2. P2 = P1V1/V2 = P1 x V1 / (1/3V1) P2 = 3P1 The new pressure will be three times the original pressure. Therefore your answer is (C). === Follow up === (D) is definitely NOT the correct answer.
Answered by pisgahchemist - Sun Oct 25 09:03:50 2009

Why is my pool pump pressure so high?
Q. My pool pump pressure seems unreasonably high. The pressure gauge on the filter indicates about 22 psi normally and 28 psi when running the solar. I have a 4.9 sq foot sand filter. The pressure doesn't change by more than one psi after backwashing. On the pressure side of the pump the water moves to the filter, then to a Zodiac Duoclear salt cell (with integrated mineral filter), then the solar control valve, then out to two pool returns (about 40 feet away) over 2 inch PE flex piping. A friend of mine has a similar system and his pressure seems to be about half of what mine is. I've checked that the gauge is not stuck and it goes all the way to zero when the system is shut off. Any suggestions?
Asked by Pete A - Fri Sep 7 12:42:38 2007 - - 3 Answers - 0 Comments

A. It sounds like your back washing is working. It drops so little because it didn't need back washing. Your solar seems to be in reasonable limits, so the only thing left is your Zodiac salt cell. Bypass that to see if that corrects the problem. Likely so.
Answered by len b - Sat Sep 8 16:36:43 2007

What happens to pressure of a gas inside a container if the temperatur of the gas decreases?
Q. is it a) the pressure cannot be predicted b) the pressure decreases c) the pressure increases d) the pressure does not change
Asked by boylen25 - Sat Mar 15 14:23:54 2008 - - 5 Answers - 0 Comments

A. As temperature increases, so does pressure and vice versa. PV/T is constant. Therefore as your temperature goes down, so does the pressure. b) is definitely your answer.
Answered by cstspeedy - Sat Mar 15 14:32:42 2008

Which pressure washer should I buy to use around the yard?
Q. I've looked at a few websites and see that I can get gas powered washers for upwards of $400 and also get small electric ones for as low as $80. I understand that the big difference seems to be the pressure that each puts out (PSI) but that's all I understand. Can I get a compressor so I can say attach a paint sprayer, a tire inflator and then attach a head so I can pressure wash? Or do I have to get a compressor for paint and air and then a pressure washer as well? I'm mostly interested in the washing part but would be nice to have an all in one solution if that is even available? Here is what I want to do...wash the cars, RV, kids bikes, driveway, vinyl siding on the house and basic yardwork type of chores. Please help me figure out… [cont.]
Asked by sirdufus69 - Thu May 10 01:48:25 2007 - - 3 Answers - 0 Comments

A. If it were me... I'd go to the local rental equipment shop and ask the guy in charge of what he thinks. Why - because he would be the one very familiar with what you'd be looking for. As that's what he rents, and is very knowledgeable about.
Answered by SoftTSoul - Thu May 10 04:14:19 2007

What is the pressure in Pa inside a container?
Q. What is the pressure in Pa inside a container if the mercury level in the manometer arm attached to the container stands 18.5cm higher than the mercury level in the manometer arm that is open to the atmosphere? The atmospheric pressure as determined by a barometer is 103,000 Pa. I know that the pressure inside a container has to be lower than 103,000 Pa, since the mercury level in the arm attached to the container is higher, meaning the atmosphere is pushing much harder. And I have to use the formula: pressure in container=height difference + atmospheric pressure. So, I converted 18.5mm into 2466.46 Pa, then added to the 103,000. The answer, then, is 105466.4638. I don't think this is logical, because now, the pressure inside the… [cont.]
Asked by honey(*_*) - Wed Jan 31 22:34:09 2007 - - 2 Answers - 0 Comments

A. Youir logic is perfect except that the height here is viewed as negative like you said since the external arm is lower. So 103Kpa - 2.47Kpa = Good job of thinking about the answer before solving - it will always benefit you!
Answered by Alan S - Wed Jan 31 23:56:55 2007

What is the difference between water pressure and air pressure?
Q. Basically I want to know if pressure is equal no matter what type of pressure it is. I've heard that 100 pounds of air pressure is like 400 pounds of water pressure (when used in piping). Will a pipe rated for 300 pounds of water pressure hold up to 300 pounds of air pressure? I am having a disagreement with some guys at work about this, so if you have a source to go with the answer that would be great!
Asked by tgcrmhsch - Thu Jan 31 22:49:53 2008 - - 2 Answers - 0 Comments

A. Water is incompressible. As soon as a water pipe cracks a little, the pressure drops instantly. When you have a compressed gas in a pipe and the pipe fails, the gas can expand and still provide pressure to the pipe fragments. Failures under these circumstances are much more dangerous. Note that a small leak in a hydraulic line can still shoot a jet an oil through you.
Answered by Ooga B - Thu Jan 31 22:55:28 2008

What blood pressure pill can a insulin dependent diabetic take ?
Q. I have tried Cozaar, Lisinopril & Diovan & had bad side effects from them & my blood pressure actually went higher. Please help, has this happened to anyone else ? I am taking Tenormin (Atenenol) now but my blood pressure is still high. What are some of the blood pressure pills other diabetic take with little side effects ?
Asked by Lotsofwork - Fri Apr 9 22:44:14 2010 - - 3 Answers - 0 Comments

A. I take Enalapril Maleate . Ten MG. a day. Bp went from 150/90 tyo 118/68...But there is a catch to this. I started to exercise 1 hour and 30 min. a day . Nordic Walking. And this is what I think really lowered my BP. Cause before I was taking 5 mg. and nothing was getting better. I have no side effects. I pay 3 1/2 cents a 5 mg. pill. I live in Thailand. Try the exercise bit. I do it everyday : Rain or Shine. How are high blood pressure and exercise connected? Regular physical activity makes your heart stronger. A stronger heart can pump more blood with less effort. If your heart can work less to pump, the force on your arteries decreases, lowering your blood pressure. Becoming more active can lower your systolic blood pressure the… [cont.]
Answered by Tin S - Sat Apr 10 05:46:56 2010

What is the pressure in atmosphere in the cabin if the barometer reading is 688mm Hg?
Q. The pressure outside a jet plane flying at high altitude falls considerably below standard atmospheric pressure.Therefore, The air inside the cabin must be pressurized to protect the passengers. What is the pressure in atmosphere in the cabin if the barometer reading is 688 mm Hg?
Asked by Rye - Wed Apr 9 12:17:14 2008 - - 2 Answers - 0 Comments

A. pressure of 1 atm at STP = 760mm Hg Pressure in plane = 688/760 = 0.905 atm.
Answered by Trevor H - Wed Apr 9 13:46:22 2008

Why does the pressure on my sears kenmore boiler keep rising above the safety pressure?
Q. I have a hotwater baseboard system and the pressure keeps rising to the point where the pressure releif valve always kicks on. I bleed the system often. The boiler has 3 zones. It is about 12 years old. I recently replaced the expansion tank. What could be wrong?
Asked by John P - Thu Nov 22 08:33:34 2007 - - 5 Answers - 0 Comments

A. not sure but you had better call a qualified repair man unless you want the boiler to go Thur the roof,
Answered by William B - Thu Nov 22 08:53:29 2007

When should we add the atmospheric pressure to a gas pressure and related?
Q. Say a tube is immersed with its head down into mercury,completely(exactl y),then is the pressure equal to pressure of air+pressure of mercury around it.Can you explain why both are included?
Asked by dork - Fri Jul 24 13:42:30 2009 - - 1 Answers - 0 Comments

A. When we speak of measuring pressure we should really speak of measuring pressure difference, and it is then a question of the zero point from which one measures. If we measure atmospheric pressure with a mercury barometer we are measuring it against the vacuum at the top of the tube, and we are therefore measuring absolute pressures. The atmospheric pressure is then 1013 (or whatever) millibars absolute. If we measure the pressure at a depth below the sea surface (or below the surface of a bowl of mercury) the reference point is the surface atmosphere, and we speak of the measured pressure as so many cm H2O (or mm Hg) above atmospheric. If, for some reason, you wanted absolute values for these depth pressures you would have to add in the… [cont.]
Answered by Peter H - Fri Jul 24 15:16:29 2009

What is the difference between air pressure and air density?
Q. Is there a difference? I know that pressure is directly related to temperature which means that when pressure rises so does the temperature but is air density different? Is air pressure only to do with particles of air or can you have a high air pressure just by compressing air. Anything else vaguely related would be great also. Thanks.
Asked by Tommy - Tue May 4 04:31:51 2010 - - 3 Answers - 0 Comments

A. Understanding air pressure The weight of the air pressing down on the Earth, the ocean and on the air below causes air pressure. Earth's gravity, of course, causes the downward force that we know as "weight." Since the pressure depends upon the amount of air above the point where you're measuring the pressure, the pressure decreases as you go higher. Air pressure is related to its density, which is related to the air's temperature and height above the Earth's surface. (Related: Understanding air density). Air pressure changes with the weather. In fact, it's one of the most important factors that determines what the weather is like. (Related: How high and low pressure affect the weather). You can do some basic weather forecasting by… [cont.]
Answered by Fran S - Tue May 4 04:35:30 2010

My well system lost pressure on my behalf, how do I gain back the pressure?
Q. I've turned the pump back on and the pressure is between 20 and 40 and the pump is not reaching the required pressure.
Asked by Danny J - Sat May 3 21:24:21 2008 - - 5 Answers - 0 Comments

A. Sounds like it is up to pressure. The pump will not turn on until the pressure drops to 20 pounds and will then turn off at 40.
Answered by Carl - Sat May 3 22:08:43 2008

What is the equation connecting systolic pressure to pulse rate?
Q. In a recent Question a User asked how pulse rate affected blood pressure, and one answer supplied the equation showing the how pulse rate and diastolic pressure are connected. I asked what the equation for diastolic pressure was, but the Question was closed before I could get an answer. Can someone tell me how pulse rate affects systolic pressure?
Asked by Henry - Sat Aug 8 06:11:00 2009 - - 3 Answers - 1 Comments

A. The equation you seek relating pulse rate (N) to Systolic pressure (Ps) is: Ps = (N x Pp x C x R) + (CO/N.C) where C is aortal wall compliance, Pp the pulse pressure, R being the total resistance presented to the flow of blood (by the vasculature extending from the aortic valve to the venous pool), and CO of course, is cardiac output. Orthodox textbooks will (quite wrongly) contend that the 1st term on the RH side of the equation should read {N.Pp.C.R - Pp/3} but this is quite incorrect, because the pulse pressure wave does no work, (apart from losses) and therefore plays no part in the driving of blood round the loop.. But it doesn't really matter anyway, because the equation works in any case, -with or without the " -Pp/3". … [cont.]
Answered by Huguette - Sat Aug 8 11:15:50 2009

What is the difference between static pressure and dynamic pressure?
Q. My teacher said that: Blowing underneath a piece of paper and watching it rise is Newton - greater static pressure underneath.( in line with velocity) Blowing on top of the paper and watching it rise is Bernoulli - lower dynamic pressure on top (at right angles to velocity). So what exactly is the difference between static and dynamic pressure?
Asked by Fred - Mon Jun 15 20:47:37 2009 - - 2 Answers - 0 Comments

A. Static pressure is the ambient pressure (as when in still air). The dynamic pressure is the pressure that you feel against your face as you speed through the air. If you place a 1 sq ft plate into wind and you measure 25 lbs of force on the plate, you have a dynamic pressure of 25 pounds per sq ft.
Answered by Bernie R - Mon Jun 15 21:05:06 2009

Can I pressure cook jars of (vermiculite and rice) twice without destroying the nutritional value of the rice?
Q. I am making a substrate for germinating plants and they need the rice for its nutrient value. I messed up and let the pressure cooker cool down overnight and now I'm wondering if I should recook it... It has to remain perfectly sterile until I use it. What would happen if you pressure cooked --canned--someting twice? Any response appreciated.
Asked by scarlett - Sun Sep 9 12:52:19 2007 - - 2 Answers - 0 Comments

A. you are in good shape... your mixture is sterile as long as you don't contaminate it now...use away
Answered by Becky B - Sun Sep 9 13:31:02 2007

What is the partial pressure of gas A expressed after equilibration?
Q. Two gases are contained in gas bulbs connected by a valve. Gas A is present in a 1 liter bulb at a pressure of 874 torr. Gas B exerts a pressure of 457 torr in a 1 liter bulb. The valve is opened and the two gases equilibrate. What is the partial pressure of gas A expressed after equilibration? Answer in torr.
Asked by beehappinow - Wed Oct 31 00:27:14 2007 - - 1 Answers - 0 Comments

A. 437 torr. Boyle's law: PV=PV 1L*874 torr.= 2L*P P=437 torr. This is the way I'll think of it, because only the volume changed to 2L. But I am not sure that this is the answer for certain. So just wait a while and see if anyone else agrees or have a better answer.
Answered by 2n^2 - Wed Oct 31 00:43:35 2007

How high the max pressure of water heater can be?
Q. Water heater has a pressure relief lever. But how high the pressure will be, then the relief leaver supposes to begin work in normal case? Does the pressure will go up 15 PSI? Thanks. Since the thread nipple at water heater is rusted into leaking and very difficult to take out, I think to use the connecting method of auto radiator and use rubber hose to connect the nipple and the cold water supply. But I think the rubber hose may strong enough to hold 60 PSI. Any idea?
Asked by Edward S - Tue Jun 3 13:33:13 2008 - - 4 Answers - 0 Comments

A. your average water pressure will be 60 psi
Answered by Adam D - Tue Jun 3 14:38:02 2008

What is the highest temperature at the lowest pressure that carbon dioxide remains in liquid form?
Q. Unanswered from 4 days ago: Let's say I need to vaporize Liquid CO2, but do not want to deal with alot of condensation, and do not want the Co2 to go supercritical, since there will be alot of heat involved in the vaporizing. What would be an optimum temp/pressure? In F and PSI please. Thanks CO2 liguid forms under pressure and at cold temperatures, solids sublime at atmospheric pressure, also super critical fluid forms at high temperature and pressure. It is possible to have CO2 liquid at 0F, under 300 PSI. I know this I am wondering how much pressure would be needed to get keep liquid at say 24F? Is this possible? If I vaporized this liquid would I risk the liquid going supercritical? Chem man those charts do not have any real… [cont.]
Asked by Jason G - Sat Jul 28 22:15:41 2007 - - 2 Answers - 0 Comments

A. -2
Answered by Nene - Sat Jul 28 22:19:06 2007

What can cause high blood pressure in a female who was perfectly fine before she gave birth?
Q. An associate of mine of normal weight and blood pressure, got pregnant and developed high blood pressure throughout her pregnancy. The moment she gave birth, the BP went back to normal. The doctor told her she should never get pregnant again. Against his advice, she got pregnant again and the high blood pressure not only came back but it stayed and has been with her since. Still a fairly normal weight, her BP can be normal one day and way the next. Any ideas on what could be causing this? It even has her doctors stumped.
Asked by blutoadmirer - Thu Mar 4 00:21:54 2010 - - 2 Answers - 0 Comments

A. A lot of times high bp is idiopathic, meaning doctors don't know the cause of it. A lot of women get preeclampsia or high bp during p/g it's quite common. As to why the high bp stayed with her after p/g there's no telling. Even just a 10% weight gain can affect bp as well as salt, caffeine ect.. If your friend loses a bit of weight, cuts salt out of her diet and stops any and all caffeine she might see improvement. But otherwise she may just need to take a simple bp med from now on. I myself have high bp and have had it for 6 years and i'm only 28. My weight is a factor and my history as a bulimic affects it too, but even when i was skinny i still had high bp. I just accept it and work to keep it down with medication,diet,exercise, and… [cont.]
Answered by Jessi Ann - Thu Mar 4 00:39:34 2010