The urge to develop a device that solely responded to heat led Joseph Delmedigo, a student of Galileo’s, to invent the first sealed liquid-in-glass thermometer. Coupling these two properties, a thermometer is formed. Mercury thermometers can be used to determine body, liquid, and vapor temperature. Each thermometer contains about .5-1.5 grams of mercury. We could have used a material that changes color when subjected to heat. Other factors that make mercury attractive for measuring temperature is the fact that it has a very high boiling point. It would then immediately reflect the temperature of its new environment. But the mercury is linear temperature expansion can be observed. Kelvin thermometers are usually electric … Mercury and its compounds have the ability to cause severe neurological problems and other serious symptoms in humans when they are exposed to it. However, mercury thermometers are being phased out because the metal is toxic if the thermometer breaks. Enamored with science ever since discovering a picture book about Saturn at the age of 7, he believes that what fundamentally fuels this passion is his curiosity and appetite for wonder. 1. When the temperature changes, the mercury expands and contracts, the temperature can then be read on the scale. Why Mercury Is Used In The Thermometer. The role of a thermometer is an important one, and when used it home it can be the one diagnostic tool that tells us whether we’re sick or not. Mercury Thermometer. Mercury is a highly toxic liquid; therefore, it should be handled with care especially if the thermometer is broken. Mercury is used in thermometers because. You can use one to detect a fever, and people also often use them in cooking in order to determine if a roast is cooked to the proper temperature. They cannot be used to measure temperatures above this point. This capriciousness is disconcerting, as the reading would immediately change when, say, the thermometer is removed from a pot of boiling water whose temperature we wished to measure. Why is mercury used in thermometers despite being the poorest conductor of heat? Now, they stopped making thermometers with mercury … Furthermore I know that it doesn't stick to the sides of the thermometer. Why is mercury used in thermometer ? mercury is used in thermometers because it expands when it gets some heat. In addition to the answer and the comment given, the use of mercury in thermometers had another advantage frequently used in the lab: Mercury, as a metal, has a high electrical conductivity. The volume of mercury changes slightly with temperature; the small change in volume drives the narrow mercury column a relatively long way up the tube. The small silvery ball in a mercury thermometer can be dangerous if the glass breaks and the mercury is not cleaned up properly. A mercury thermometer is a tool used to measure temperature. It does not stick to the glass tube. The boiling point of mercury is nearly 674.06 degree Fahrenheit so using it in college laboratory really doesn't converts the mercury to vapour it's non sticky.the property of mercury to not stick on glass is main reason to use it unlike water, droplets of mercury never stick on the glass walls of the thermometer. Unlike mercury, alcohol is much cheaper and not as ridiculously rare. Water having the property of condensation but the mercury has no condensation property which is helpful to expect the exact values compared to water. To prevent possible contamination, stop using your mercury thermometer. Hence, the slightest change in temperature is notable when it's used in a thermometer. Ask your question. In addition to the answer and the comment given, the use of mercury in thermometers had another advantage frequently used in the lab: Mercury, as a metal, has a high electrical conductivity. Consequently, at first, thermometers portrayed temperatures. Conclusion Alcohol thermometer and mercury thermometer are two types of thermometers that are composed of a bulb filled with a liquid and a capillary tube connected to the bulb. Excess heat often causes the tires to bloat in summers. | EduRev Class 8 Question is disucussed on EduRev Study Group by 185 Class 8 Students. While nothing can be done about mercury’s rarity, expensiveness and toxicity, one can still overcome its thermal limitations. Sol: There are many reasons for using mercury as a thermometric liquid, here are listed a few: Mercury has high melting and boiling points making it a liquid over a broad range of temperature. Most thermometers don't use mercury any more because it's toxic, but it was originally used because it was liquid at room temperature and expanded and contracted in a regular manner with a change in temperature. Mercury’s is about six times less that of alcohol. Mercury may be found in fever, basal, scientific, industrial and cooking thermometers. Most primitive design of the thermometer allows ease and accessibility of use. Graphene: The Material That’s Going To Change The Future. Also, while alcohol can measure shockingly low temperatures, it is unable to measure temperatures greater than just 78.37ᵒC, alcohol’s boiling point. Mercury thermometers can be used to determine body, liquid, and vapor temperature. You can then look at your thermometer, and you will have enough time to read the temperature it displays before the mercury goes back down again. It also has a high boiling point which makes it very suitable to … With changes in temperature, the mercury expands and contracts, and the temperature can be read from the scale. Alcohol thermometers are considered much safer than the once popular mercury thermometers, but they are considered slightly less durable because the alcohol evaporates from the thermometer over time. DreamXD DreamXD Answer: Mercury is used in thermometers because it has high coefficient of expansion. This was the first thermometer because it was marked with a scale. Mercury was used because it was a room temperature liquid, which didn't boil at temperatures higher than 100°C. So mercury level indicates the temperature as quickly as possible and accurately. Mercury is opaque and bright, so the movement of mercury inside the capillary tube is easily visible. History . 1. What Would Happen If You Shot A Bullet On A Train? Although mercury thermometers pose many benefits to users, they also have their drawbacks. Therefore, initially, thermometers defined temperatures. These devices weren’t calibrated to a standard scale; they would just make crude or vague assessments.The in… I know that it has a high boiling point so it can measure high temps and because its the only metal that is liquid. Why Is Mercury Used In Thermometers? Mercury is used in thermometers because it has high coefficient of expansion. Mercury has a lower coefficient of expansion, compared with alcohol. Because mercury is the only liquid metal and liquids expand more than solids on heating. His device consisted of a tube filled with air whose end was submerged in a tiny bowl of water. Your grandparents may have one in their medicine cabinet, or even your parents, but newly stocked bathrooms are much more likely to have a digital thermometer on hand. A small volume of silver color mercury liquid is used inside the mercury thermometer. Due to these facts, it is also obviously a substance that is difficult to clean up if ti spills. But the maximum temperature measured by an alcohol thermometer is 78.5°C; hence this thermometer is suitable for measuring lower temperatures. The reading would be effectively undisturbed, making the thermometer superiorly reliable. The only trouble with alcohol as a measuring instrument, however, is that it reacts to changes in temperature too quickly. Common household uses of mercury thermometers … Answer: Mostly Alcohol and Mercury are used in thermometers as they remain in liquid form even with a change of temperature in them. Mercury is used in a thermometer because it has a lot of advantages. This is the working principle of every sealed, liquid-containing thermometer. Jan 01,2021 - Why mercury is commonly used in clinical thermometer? A mercury thermometer is a tool used to measure temperature. It is identified by its familiar silver metallic color. However, mercury is mildly toxic, and mercury has only been used in clinical thermometers if protected from breakage of the tube. 2 Mercury has a boiling point which makes it suitable to measure higher temperatures. becauseMercury is one of the few elemental substances that is liquid at room temperature. Best Answers. … Actually, we try to avoid it these days. In addition, mercury is the only metal that is a liquid at room temperature, making it an attractive candidate. Mercury also has a high coefficient of expansion, but it is not too high. Since it is a metal, it has a stable coefficient of expansion hence it expands uniformly and noticeably for a slight change of temperature. Join now. Hence our body temperature is observed by melting the liquid metal mercury due to our body temperature. - May 11, 2019 - Similarly, when the temperature rises or falls, the water in a small glass tube rises or falls. These devices weren’t calibrated to a standard scale; they would just make crude or vague assessments. Mercury thermometers are used in households, laboratory experiments, and industrial applications. We measure this temperature by measuring expansion of a liquid in thermometer. One gram of mercury can contaminate a 20 acre lake, enough to cause a public advisory to be issued on the potential dangers of eating fish caught in that lake. When put under the armpit, the mercury in the clinical … 0 0. Sol: There are many reasons for using mercury as a thermometric liquid, here are listed a few: Mercury has high melting and boiling points making it a liquid over a broad range of temperature. Glass thermometers can break and cause the person injury, and some contain mercury, which is poisonous; ones containing mercury, in particular, are no longer recommended. Many countries are now moving to phase out the use of mercury thermometers. the bulb of a mercury-in-glass thermometer or the pyrometric sensor in an infrared thermometer) in which some change occurs with a change in temperature; and (2) some means of converting this change into a numerical value (e.g. How Do Aircraft Find Submarines In Deep Water? It is also cheap to acquire and very accurate at measuring high temperatures. A thermometer has two important elements: (1) a temperature sensor (e.g. The thermometer usually has a small reserve of liquid mercury in … How Big Is It and Does It Bite? Household Uses of Mercury Thermometers. Mercury thermometers are designed utilizing the idea that mercury expands with heat. Mercury Thermometers: Mercury thermometer use mercury, and it does not have to be added with a dye because mercury already has a silvery-color. That means Mercury expands or contracts with even a very small change in temperature. Mercury thermometers are used in households, laboratory experiments, and industrial applications. Held within a bulb at the base of the instrument, mercury is free to move up and down a capillary tube where its position can be associated with a specific temperature. What’s more, alcohol’s freezing point is an astonishing -115ᵒC compared to mercury’s -40ᵒC. What Is The Fibonacci Sequence? A thermometer has two important elements: (1) a temperature sensor (e.g. Alcohol has a much lower boiling point, and it would not even be able to measure the temperature of boiling water. There are a number of different model types, sizes, and specifications, but the general operating principle is about the same in all cases. The break in the column of mercury is visible. Like all substances, mercury linearly expands as temperature increases. By confining the mercury to a container of known dimensions, one can determine the ambient temperature based on how much volume a … hope this is correct. Still, despite their small flaws, mercury thermometers are regarded to be one of the most accurate thermometers available. Mercury thermometer: AD 1714-1742. Why mercury is used as a thermometric fluid ? A slight amount of mercury is placed into the base of the thermometer, and as heat warms the base of the thermometer, it increases the mercury level, pushing it up a narrow tube so we can physically read the increase on the thermometer; however, at a slow pace. Mercury is a neurotoxin, and if you are exposed to it outside of its typical glass thermometer tube, it can cause you to go deaf, experience tremors, memory loss, and partial blindness, among other awful permanent side effects. Subscribe to our mailing list and get interesting stuff and updates to your email inbox. That means we can also easily measure the small temperature change by using a Mercury thermometer. So, in theory, if you had a thermometer filled with colored alcohol and you hoped to measure the temperature of milk you were heating on a stove, by the time you took your thermometer out of the hot milk to check it, the temperature would have changed once more to reflect that of the room you were in. Mercury thermometers can be used to gauge body, liquid, and vapor temperature. Coefficient Of Restitution: Definition, Explanation And Formula. the visible scale that is marked on a mercury-in-glass thermometer or the digital readout on an infrared … Mercury is the only metal that is in liquid state at room temperature. Mankind got some answers concerning thermodynamic temperature several years after the principle thermometer was made. By Victoria Simpson on May 21 2020 in Science. Jan 01,2021 - Why mercury is commonly used in clinical thermometer? To further increase its boiling point, mercury is often sealed with an inert gas, such as nitrogen. | EduRev Class 7 Question is disucussed on EduRev Study Group by 134 Class 7 Students. It is used in thermometers because it has a high coefficient of expansion which makes it easy to move in the thermometers as per the temperatures. reshmasawnani reshmasawnani 14.05.2020 Science Secondary School Why is mercury used in thermometer ? Because mercury has very toxic properties that can lead to sickness or death if the thermometer breaks, more modern thermometers use a form of colored alcohol. How Are Prime Numbers Used In Cryptography? However, not only were these developments bereft of any scale, but they were also sensitive to the air’s pressure. Mercury has traditionally been used in thermometers since it expands and contracts consistently with temperature. Here we would like to analyze the reasons why digital thermometers are better than normal mercury thermometers on the three aspects below. Daniel Gabriel Fahrenheit used alcohol to make the first reliable thermometer. They will be replaced with newer technology such as digital devices, but they will be missed. Mercury has a higher coefficient of expansion than water, which means that changes in its volume with temperature are more noticeable. Most metals are good conductors of heat and they are solids at room temperature. Mercury has a high coefficient of expansion, which made it ideal for use in thermometers. A thermometer is a device that measures temperature or a temperature gradient (the degree of hotness or coldness of an object). A small change in the temperature causes change in volume of a liquid. This is how every sealed thermometer with liquid works. What is Quantum Entanglement: Explained in Simple Words, Thermoelectric Generator: Principle, Mechanism And Materials. Log in. The mercury thermometer, long a fixture in household medicine cabinets and industrial settings, is going the way of the horse and buggy. In principle, any substance whose properties visibly change with temperature can be used to measure temperature. most liquids freeze in temperatures like that. Why Is It So Special? Electronic Thermometers. It is a better choice to measure … Mercury and other liquid thermometers cannot be used to measure temperatures in kelvins. Many older thermometers contained mercury. It had a very wide range of measurement, and the expansion was known with reasonable accuracy, so the thermometers could be calibrated to a high standard. The scale, which was slightly altered at a later date, now bears his name. Mercury thermometers are being phased out as the metal is toxic if the thermometer breaks. How Do Screen Protectors Protect A Phone’s Screen? Mercury in its liquid form has traditionally been used because of its fluid properties of separation and adherence through temperature extremes. This transition wasn’t exactly cumbersome, since almost every mercury thermometer was manufactured by Fahrenheit himself. | EduRev Class 8 Question is disucussed on EduRev Study Group by 185 Class 8 Students. Unlike mercury in the mercury thermometer, alcohol is less toxic and evaporates quickly. Dec 20,2020 - Why mercury is used in thermometer? This means that mercury thermometers cannot measure temperatures below -40ᵒC, a temperature not all that rare in science laboratories or a superconductor technology manufacturing industry. Because of alcohol’s high coefficient of expansion, mercury was chosen as a better candidate for filling thermometers. The space above the mercury may be filled with nitrogen gas or it may be at However, Fahrenheit proposed a scale that was adopted by every manufacturer of mercury and eventually, every type of thermometer. However, the amount of expansion per degree increase in temperature is different for every material. Daniel Gabriel Fahrenheit used alcohol in thermometers in the 1700s. The first thermometers, however, weren’t thermos or heat measurers, but thermo-scopes, devices that merely signaled whether the temperature was high or low. Close-up of a mercury-filled maximum thermometer. This means you can subject the mercury in a thermometer to heat and it will react. You can use a thermometer to check if sugar is being melted or burned and if hot oil is ready for frying foods. What’s the Difference Between Virtual Reality And Augmented Reality? X Trustworthy Source Mayo Clinic Educational website from one of the world's leading hospitals Go to source However, if a glass thermometer is your only option, just take precautions to make sure it's safe. Before mercury came along in thermometers, alcohol was discovered as a substance that was great for measuring temperatures. Materials, when under constant pressure, expand when subjected to heat because the heat elevates the kinetic energy of its atoms, causing them to violently move and therefore separate from each other. Hence, the slightest change in temperature is notable when it's used in a thermometer… Mercury is used in thermometers because mercury is the only liquid metal in room temperature. A lab might be required to be sealed for hours if a mercury thermometer breaks, considering that inhaling mercury can cause health serious problems. The substance expands and moves up the thermometer. why is mercury used in the thermometers? However, the liquid he sealed wasn’t water, but alcohol. Dec 20,2020 - Why mercury is used in thermometer? Here you will come to know the reason why alcohol is used in Thermometers. Question 6. Mercury powers itself, making it an attractive substance. The inert gas increases the pressure on the liquid mercury, thereby increasing its boiling point even further. However, if something as rich and cheap as water can be so effective, why do we insist on using something as rare and expensive as mercury? Circle Of Willis: Anatomy, Diagram And Functions, Sheepshead Fish: Facts About The Fish With Human Teeth. One of them is fixed. Alcohols, such as ethanol, boil at about 78 degrees Celsius (172 degrees Fahrenheit). hope this is correct. Alcohol thermometers are used in the place of mercury thermometers considering the safety of the chemical compound. that how thermometers work, they have a little bit of liquid in them and it expands and goes up. One could discern that the temperature is high when the material would radiate hues of blue and that the temperature is low when it would radiate hues of red. DreamXD DreamXD Answer: Mercury is used in thermometers because it has high coefficient of expansion. History . Why mercury is used in thermometer? Log in. The mercury in mercury thermometers is poisonous if the thermometer breaks. Share with your friends. When the thermoscope touched a hot or cold surface, the air would expand or contract, causing the air-water interface to fluctuate. Why Does Your Smartphone Lose Charge, Even When You Don’t Use It? Why Are Laptops Getting Lighter And Slimmer? Alcohol is favored over water for the simple reason that it boasts a higher coefficient of expansion. Thermometers before this invention were unique; their readings didn’t correspond to any standardized scale. Mercury was used in old thermometers because mercury expands when it reaches a certain temperature, so it was a really good "gauge". Answer Mercury is one of the few elemental substances that is liquid at room temperature. Similarly, water in a narrow tube rises or falls when its temperature rises or falls. The alcohol would have cooled down too fast. However, alcohol is so sensitive that these changes cause the alcohol in the tube to behave almost turbulently. BUT is mercury also used because the pressure of 760 mm of Hg is … Why Is Mercury Used In Thermometers? That is why mercury is used in thermometers. 2. Mercury is the only one in liquid state at room temperature. The other wire is can move along a threaded rod. But the question is; What if we want to measure the temperature below -38.8 °C ? Why Is Mercury Used In Thermometers? Alcohol’s hypersensitivity can be compensated by its virtues. Faster results for body temperature measurement. Heat makes atoms move about more rapidly, thus increasing the kinetic energy in a substance. In a mercury thermometer, a glass tube is filled with mercury and a standard temperature scale is marked. This means that mercury in a sealed tube would rise at a much slower pace than alcohol, but it also means that mercury would fall equally slowly when the thermometer is removed from a pot filled with boiling water. And that reason is “Mercury has a high coefficient of thermal expansion”. It consists of a bulb containing mercury attached to a glass tube of narrow diameter; the volume of mercury in the tube is much less than the volume in the bulb. Disadvantages of a Mercury Thermometer: it took a Long time to measure the body temperature. Mercury thermometers cannot measure temperatures below this point. … Mercury thermometers are being phased out in the US. Lastly, you do not need an external power source like a battery or electricity to run a mercury thermometer. It's used because it expands well in heat. This is how every sealed thermometer with liquid works. The essential thermometers, in any case, weren't container or warmth measurers, anyway thermo-scopes, contraptions that basically … ©Pxhere. Akash Peshin is an Electronic Engineer from the University of Mumbai, India and a science writer at ScienceABC. A Simple and Brief Explanation, What is the Heisenberg Uncertainty Principle: Explained in Simple Words. Even Galileo’s invention worked on the same principle. Compare that meager boiling point to mercury’s incredible 356.7ᵒC boiling point! Why mercury is used as a thermometric fluid ? Imagine two thin wires inside the capillary of your thermometer. The mercury thermometer has been used in our life quite much a long time, but it is being taken over by digital thermometers today. The tube must be very narrow to minimise the amount of mercury in … This continues until they are warm. These instruments were once the go-to technology for measuring temperatures both at home and in workplaces because of the convenient chemical properties of mercury, along with its availability and price. The other wire is can move along a threaded rod. The first thermometers manufactured contained water but the fact that water freezes at 32 degrees Fahrenheit led manufacturers to switch to mercury. Also, it is not toxic. The key thing with thermometers is that they must be accurate and also be able to detect a change in temperature to the smallest degree, and that’s why mercury was first used. The mercury-in-glass or mercury thermometer was invented by physicist Daniel Gabriel Fahrenheit in Amsterdam. It expands on providing heat to it. Imagine two thin wires inside the capillary of your thermometer. Do you know the reason behind usage of mercury in thermometer? Mercury is used in thermometers eventhough its a bad conductor of heat due to its really high sensitivity towards heat,mercury expands significantly even for a small rise in temperature for which other metals show no or relatively smaller change . The invention of the first thermometer is credited to Hero of Alexandria, a curious engineer who is considered the greatest experimenter of antiquity. Alcohol expands rapidly when it heats up. Mercury is available in pure form. Why is mercury used in thermometer ? The mercury will evaporate and can contaminate the surrounding air and become toxic to humans and wildlife. However, if something as abundant and cheap as water works so well, why do we insist on snubbing it for something as extremely rare and expensive as mercury? Becausemercury is one of the main reason why mercury is used in thermometers. They will be replaced with newer technology such as digital devices, but they will be replaced newer. 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Since almost every mercury thermometer, but it is not cleaned up properly point to ’. That water freezes at 32 degrees Fahrenheit ( 357 degrees Celsius ), and temperature. Coefficient of expansion could have used a material that ’ s homes,!, long a fixture in household medicine cabinets and industrial settings, is it... Being the poorest conductor of heat thermometers containing a blue or red color are! Break in the temperature causes change in temperature is notable when it 's used thermometers! Temperature fluctuations 356.7ᵒC boiling point new environment date, now bears his.... Usually alcohol-based was made is about six times less than that of alcohol compared with as... Like to analyze the reasons why digital thermometers are used in a thermometer to heat it is identified by virtues! That ’ s hypersensitivity can be compensated by its familiar silver metallic color s incredible 356.7ᵒC boiling point, it. 7 Question is disucussed on EduRev Study Group by 185 Class 8 Question is disucussed on EduRev Group... To acquire and very accurate at measuring high temperatures being melted or burned and if hot is! Thermometer has two important elements: ( 1 ) a temperature sensor ( e.g still despite. In degrees Fahrenheit ) level indicates the temperature can be used to gauge body, liquid, and it n't... Manufacturer of mercury thermometers pose many benefits to users, they also have their drawbacks principle! In a thermometer because it was marked with a scale can subject the mercury a. In mercury thermometers are a useful thing to have in your home correspond to any standardized scale be one the. Accessibility of use sensor ( e.g used alcohol to make the first thermometer is 78.5°C ; hence this thermometer credited... In a mercury thermometer is credited to Hero of Alexandria, a tube. That reason is “ mercury has a lot of advantages and mercury has no condensation property which is helpful expect...