why would you use an alchol thermometer rather than a mercury one to measure the temperature in a freezer?
964556
Mercury freezing point: -38.72 degrees C\n\nA mercury thermometer will probably lose accuracy somewhat above the freezing point, because as one approaches the phase\ntransition from liquid to solid, one loses the linear dependence\nof the column length on temperature.\n\n\nAlcohol's freezing point is -117 degrees therefore it doesn't get cold enough to freeze alcohol.\n\nTherefore alcohol is better at low temperatures
642524
If you have a freezer that will lower the temp. of carbon dioxide to its freezing point you're straight in. Somewhere in the neighborhood of -125 Fahrenheit
983788
A waist high horizontal freezer will be better at keeping cold air in because of the laws of convection.\nWarm air rises, so if you open your freezer-which has cold air- the cold air will stay at the bottom and inside the freezer unless the air outside is less than the temperature of the freezer ;)\nthe vertical freezer, you will lose cold air when you open it because the air will flow out of it and "fall out of the freezer"  making warm air rush in to compensate.\n\nIn terms of efficiency, the horizontal freezer is a better design, however, due to space restrictions, some people prefer vertical freezers over the horizontal ones.
1025750
A liquid-in-glass thermometer uses a column of liquid, usually mercury or alcohol, that is contained in long glass tube. The length of the liquid column changes with temperature. A scale is marked on the glass tube. In a common mercury thermometer, the scale is normally given 100 divisions . Zero on the scale corresponds to the melting point of ice and the 100 corresponds to the boiling point of water. This liquid-in -glass thermometer is therefore capable of measuring temperatures in the range zero to 100 degrees celsius.\n\nThe clinical thermometer is just a special type liquid-in-glass thermometer. However its use is for clinical purposes eg measuring body temperature. That is why it is called a clinical thermometer. The clinical thermometer uses mercury, but it is different from the common mercury thermometer in a number of ways. It is designed to read the range of body temperatures so its scale has a range of only a few degrees, usually from 35 to 42 degrees Celsius. Another difference is that it has a small bulb and a much narrower mercury column. This makes it very sensitive to small changes in temperature. The clinical thermometer also has a kink in the tube above the bulb. When the thermometer is removed from the body, the mercury starts to contract. The kink in the tube causes the mercury thread to break away from the mercury in the bulb. A column of mercury is left above the kink and this enables the temperature to be read accurately even when the thermometer is no longer in contact with the body. Another difference is that clinical thermometer has a bulge in the glass. It is more triangular in shape than the common mercy thermometer. The bulge acts as a lens, making it easier to see the narrow thread against the scale. I hope this helps.  \n\n\n\nDictionary \nclinical thermometer\nn.\nA thermometer used to measure body temperature, especially a small glass thermometer designed with a narrowing above the bulb so that the mercury column stays in position when the instrument is removed from the body.\n\n  Medical \nclinical thermometer\nn.\nA thermometer having a graduated glass tube with a bulb containing a liquid, typically mercury or colored alcohol, that expands and rises in the tube as the temperature increases.
461446
I found that cold water (38 degrees Fahrenheit) froze faster than hot water out of the tap (125 degrees F). I chose these two temperatures because (1) they were pretty much what the average amateur ice-cube maker would have readily available and (2) I couldn't find a mercury thermometer that went higher than 125 degrees.\n\nJearl, who is not afflicted with penny-pinching editors like some of the rest of us, was able to get his mitts on a thermocouple that could measure as high as the boiling point, 212 degrees F. He found that water heated to, say, 195 degrees would freeze three to ten minutes faster than water at 140-175 degrees. (There were differences depending on how much water was used, where the thermocouple was placed, and so on.) \n\nJearl suggested that the most likely explanation for this was evaporation: when water cools down from near boiling to the freezing point, as much as 16 percent evaporates away, compared to 7 percent for water at 160 degrees. The smaller the amount of water, of course, the faster it freezes. \n\nIn addition, the water vapor carries away a certain amount of heat. To test this theory, Jearl covered his lab beaker with Saran Wrap to prevent water vapor from escaping. The freezing rate difference was greatly diminished. Conceivably convection (motion within the water) also plays a role.\n\nFascinating as all this no doubt is, all it basically proves is that very hot water freezes more slowly than very VERY hot water. The ordinary fumbler in the fridge, on the other hand, is dealing with temps more like the ones I was measuring, in which case cold freezes faster than hot. I rest my case.
176041
The most commonly utilized sensor for measuring temperature are still the mercury thermometers. Maximum and minimum thermometers use mercury and alcohol. Bimetallic thermographs are the most common mechanical temperature recorders. They are easy to read and maintain. However, mechanical thermographs do require verification and adjustment of the position of the pen recorder. These instruments are installed in shelters that are naturally ventilated.
469919
Sounds like a trick question. In the north we know that putting salt on ice makes it melt. In the arctic regions only the salty sea water is still water. The ice and snow are actually fresh water. Salt lowers the temperature that water freezes at. However, if you can freeze dry the salt it will separate from the water. This is the method that's used to filter Ice Beer. So technically you could if done right but just freezing it is a difficult process because you'll need something very very cold as a coolant. This would be a good series of experiments if you can get someone that can handle dry ice (frozen C02).
1029887
This might help\nhttp://www.labxnews.com/labxnews185.htm\n\nor\n\nChiller Assembly &\n® Operating Instructions\nModel 75 Viscometer\nCHILLER ASSEMBLY\nThe two modes of operation for the Model 75 Viscometer are: (1) standard heat with tap water cool-down mode and (2)\nchilled sample mode.\nFor most efficient operation in the chilled sample mode, enter the desired temperature using the front panel keypad, the\nsample temperature will be indicated on the LCD readout.\nChiller operation:\nRefer to Fig. B.\nDisconnect the Drain Line from the “Drain” connection on the manifold, and replace with the chiller Liquid In line.\nConnect the Liquid Out line to the “Chiller” connection on the manifold. The “Water Inlet” connection on the remote test\nstation can remain connected as the internal solenoid valve will stop tap water from entering the unit.\nSet the chiller operating temperature 4?C to 8?C colder than the desired sample temperature (this will speed-up the cooling\nprocess). When the sample temperature is within this 4?C to 8?C range, change the chiller temperature setting to with-in\n2?C below the desired sample temperature.\nNOTE: The coldest temperature that can be set on the chiller is minus 12?C.\nThe chiller assembly can cool a 200 Centipoise silicone calibration fluid from room temperature to -7?C in less than 30\nminutes (with sample stirred at 40 RPM). When the sample is maintained at a temperature below freezing for any length of\ntime, an ice shell builds around the cell holder. This ice can be heated off or allowed to slowly melt off, but in either case a\nconsiderable amount of water will accumulate on the base plate.\nA mixture of 50% ethylene glycol (P/N F4173) and 50% distilled water (P/N 52717) can be used as the chiller coolant. This\nmixture should be replaced after three months of service.\nDuring operation of the chiller, the pressure gauge at the outlet should read in the 15 - 25 PSI range. A pressure reading\nbelow 15 PSI indicates: (A) a possible leak in the system, or (B) the bypass valve has been opened too much. A reading\nabove 30 PSI indicates: (A) the possibility of an obstruction, or (B) the bypass valve is closed too much.\nThe use of the cell insulator cap (P/N C6121) is required for sample temperature equilibrium, and prevents an ice shell from\nforming on the top cap. The cell insulator cap must be removed for heated operation as its upper limit is 120?C before\nmelting.\nStandard heated sample/tap water cool down operation:\nRefer to Fig. A\nConnect the Water Drain line to the “Drain” connection on the manifold. The Tap Water In line should be connected to\nthe “Water Inlet” on the manifold. The liquid out line from the chiller can be left connected to the “Chiller Inlet” on the\nremote test station during the heating operation, as the check valve will prevent contamination of chiller coolant.\nPart No. E10890001EA Rev. -\nCHILLER SPECIFICATIONS:\nPower Required………………8 amps at 115VAC, 60hz\nReservoir………………………0.5 gallon (2 liters)\nPumping rate………………….1.6 gallon per minute at 45-60 psig\nWeight………………………….80 pounds\nDimensions……………………13” X 21” X 19”
907332
Different types\nA variety of thermocouples are available, suitable for different measuring applications (industrial, scientific, food temperature, medical research, etc.).\n\nType K (Chromel (Ni-Cr alloy) / Alumel (Ni-Al alloy)) \nThe "general purpose" thermocouple. It is low cost and, owing to its popularity, it is available in a wide variety of probes. They are available in the −200 °C to +1200 °C range. The type K was specified at a time when metallurgy was nowhere near as advanced as today and consequently characteristics vary considerably between examples. There is another problem in that one of the consituent metals is magnetic (Nickel). The characteristic of the thermocouple undergoes a step change when a magnetic material reaches its Curie point. This occurs for this thermocouple at 354°C. Sensitivity is approximately 41 µV/°C. \n\nType E (Chromel / Constantan (Cu-Ni alloy)) \nType E has a high output (68 µV/°C) which makes it well suited to low temperature (cryogenic) use. Another property is that it is non-magnetic. \n\nType J (Iron / Constantan) \nLimited range (−40 to +750 °C) makes type J less popular than type K. The main application is with old equipment that cannot accept modern thermocouples. J types cannot be used above 760 °C as an abrupt magnetic transformation causes permanent decalibration. Type J's have a sensitivity of ~52 µV/°C \n\nType N (Nicrosil (Ni-Cr-Si alloy) / Nisil (Ni-Si alloy)) \nHigh stability and resistance to high temperature oxidation makes type N suitable for high temperature measurements without the cost of platinum (B, R, S) types. They can withstand temperatures above 1200 °C. Sensitivity is about 39 µV/°C at 900°C, slightly lower than a Type K. Designed to be an improved type K, it is becoming more popular. \n\nThermocouple types B, R, and S are all noble metal thermocouples and exhibit similar characteristics. They are the most stable of all thermocouples, but due to their low sensitivity (approximately 10 µV/°C) they are usually only used for high temperature measurement (>300 °C).\n\nType B (Platinum-Rhodium/Pt-Rh) \nSuited for high temperature measurements up to 1800 °C. Unusually type B thermocouples (due to the shape of their temperature-voltage curve) give the same output at 0 °C and 42 °C. This makes them useless below 50 °C. \n\nType R (Platinum /Platinum with 13% Rhodium) \nSuited for high temperature measurements up to 1600 °C. Low sensitivity (10 µV/°C) and high cost makes them unsuitable for general purpose use. \n\nType S (Platinum /Platinum with 10% Rhodium) \nSuited for high temperature measurements up to 1600 °C. Low sensitivity (10 µV/°C) and high cost makes them unsuitable for general purpose use. Due to its high stability type S is used as the standard of calibration for the melting point of gold (1064.43 °C). \n\nType T (Copper / Constantan) \nSuited for measurements in the −200 to 350 °C range. The positive conductor is made of copper, and the negative conductor is made of constantan. Often used as a differential measurement since only copper wire touches the probes. As both conductors are non-magnetic Type T thermocouples are a popular choice for applications such as Electrical Generators which contain strong magnetic fields. Type T thermocouples have a sensitivity of ~43 µV/°C \n\nThermocouples are usually selected to ensure that the measuring equipment does not limit the range of temperatures that can be measured. Note that thermocouples with low sensitivity (B, R, and S) have a correspondingly lower resolution.
925972
Antifreeze is usually ethylene glycol, however a non-toxic version of antifreeze is available, and the chemical composition of that is propylene glycol.\n\nEach of these is made of 50% water and 50% glycol to make the freezing point approx. -40 degrees celcius (also -40 F).\n\nI hope this helps!
15150
Actually, you can use many other materials for a thermometer, not just mercury.   Mercury is nice because it has properties that make it easier to build a more practical thermometer than the others.   For one it is liquid at room temperature.    Mercury would not be a good material for a thermometer below it's freezing point (see www.webelements.com for details)    Assuming we want thermometer for measuring temperature variations around room temperature, then the other properties of mercury, that is, its temperature expansion coefficient and pressure compressibility, are just right so it will expand predictably over the approximately 1 or 2 inch range that it in your thermometer.    \n\nHope that wasn't too long winded.
182238
a plastic cover on a bowl of ice will keep the ice frozen for a longer time since it does not transfer heat as quickly as foil.  You can prove this using two small bowls of ice.  Measure the surface temperature of each every minute for ten minutes and record the results.
171528
What flasks are we talking about here?\nAre there choices to choose from that you did not post?\n\nTemperature is a measure of the average kinetic energy of the particles, the higher the Average KE, the higher the temperature.  Perhaps that will help you.
977052
You need a variable in any experiment to compare results. Perhaps you could use cold (ice) water in one container, warm in another and hot or boiling in another. You can then make your prediction on which will dissolve first and have an experiment that will verify whether you have made an accurate prediction.
301398
Absolute zero is important because it is very likely to be the lowest temperate possible, and is most likely unobtainable. Knowing it is useful because it makes calculations involving temperature simple to deal with. Personally I wouldn't want to try anything like quantum thermodynamics using celcius or fahrenheit because the temperatures below zero would most likely turn out to be a lot tougher to deal with.
352668
it has more to do with the differant tempatures\nto put a light in the freezer you need to shield it from the frozen tempatures\n\nin the fridge this is nota prob since tempatures are above 32 deg fahrenhiet
767726
The previous responder brings up excellent points, particularly about the method relying on how good the analyst is.  This is highly true!   However I would add, that gravimetric methods are typically more ACCURATE for the following reasons:\n\n1.  Errors associated with volume measurement (loss in transfer, parallax, spillage, over-titration, etc.) are reduced in gravimetric measurements.  In most gravimetric measurements, you WEIGH a final product, which either IS the compound of interest, or is stoichiometrically related to it.\n\n2.  Gravimetric methods are less sensitive to temperature than volumetric methods.\n\n3.  While BOTH types of methods are subject to sample loss, gravimetic methods are less so.  (Note:  This is less true if the analyst is a clutz.   Goes very well with the previous poster's comment!)\n\n4.  A mass is easier to reproducibly determine than a concentration.   (Any day of the week!)\n\n5.  A mass is easier to STANDARDIZE than a concentration.  Again there are errors associated with both, we concede, but mass is generally easier to deal with.  \n\n6.  You will more likely encounter limits (of sensitivity) in volume measurements than you will in  mass measurements, depending on how your lab is equipped.  \n\nThese are a few thoughts, I'm sure there are others.