Why Mercury Is Used In Thermometer?
Mercury is the only one in liquid state at room temperature. It’s used in thermometers because it has high coefficient of expansion. Hence the slightest change in temperature is notable when it’s used in a thermometer. It also has a high boiling point which makes it very suitable to measure higher temperatures.Feb 11 2007
Why do we use mercury thermometer?
Mercury is the only metal that is in liquid state at room temperature. 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. Mercury has a boiling point which makes it suitable to measure higher temperatures.
Why mercury is used in thermometer than alcohol?
There is a technical reason for using mercury in clinical thermometers. Mercury has a greater coefficient of thermal expansion than alcohol. This means a column of mercury will expand and rise more than a column of alcohol for the same temperature change. As a result you can get finer readings with mercury.
Why we prefer mercury to be used in thermometer give any five reasons?
- It expands uniformly when heated.
- It has low specific heat capacity.
- I has a high boiling point (357 °C) and a low freezing point (-39 °C).
- It is a good conductor of heat.
- It does not stick to the walls of the glass tube.
- It is opaque and shiny and hence clearly visible.
Why is mercury used in thermometer and water is never used?
The melting point of water is 0oc but mercury freezing point (melting point) -38.83oc the boiling point of the mercury is 356.73oc. The water boiling point is 100oc. … This is main reason to use of mercury in the thermometers.
What is a mercury thermometer?
A mercury thermometer is used to measure the temperature of the human body. It consists of mercury-filled in a glass capillary tube where a temperature scale is marked in degree Celsius or Fahrenheit. The mercury inside the tube expands or contracts based on the changes in temperature readings.
What is the principle of mercury thermometer?
Mercury thermometers are based on the principle that liquids expand when heated and contract when cooled. So when the temperature increases the mercury expands and rises up the tube and when the temperature decreases it contracts and does the opposite.
Why is mercury not used in thermometers anymore?
The reason: Mercury released into the environment from a broken thermometer is highly poisonous. … So government and state agencies have mounted campaigns to end the use of thermometers that contain the liquid metal. Federal and state authorities have lobbied since 2002 for bans on medical mercury thermometers.
Does a thermometer have mercury?
Why is mercury used in thermometer give any two reasons?
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. Mercury has a boiling point which makes it suitable to measure higher temperatures. … The mercury expands and contracts with the changes in the temperature.
What is used instead of mercury in thermometers?
Ethanol-filled thermometers are used in preference to mercury for meteorological measurements of minimum temperatures and can be used down to −70 °C (−94 °F). The physical limitation of the ability of a thermometer to measure low temperature is the freezing point of the liquid used.
Is it illegal to have a mercury thermometer?
Those days have passed. Since 2001 20 states have banned mercury “fever thermometers” for medical use and regulations tighten every year. … But as of today the federal government has more or less killed the mercury thermometer in the United States—NIST has announced it will no longer calibrate mercury thermometers.
Why alcohol is used in thermometer?
Alcohol thermometers are used rather than mercury thermometers in very cold regions because alcohol has a lower freezing point than mercury. … If it freezes it won’t move in the tube so a liquid must be used that has a freezing point that’s lower than the temperature it’s measuring.
What is mercury thermometer and its uses?
In a mercury thermometer a glass tube is filled with mercury and a standard temperature scale is marked on the tube. With changes in temperature the mercury expands and contracts and the temperature can be read from the scale. Mercury thermometers can be used to determine body liquid and vapor temperature.
Which is better mercury or digital thermometer?
1. Digital thermometers provide faster results. Digital thermometers provide fast results as opposed to mercury thermometers whose readings are slower to realize because you have to wait for the mercury to heat and then slowly rise to display the temperature.
Which law is used in thermometer?
Do mercury thermometers expire?
Why is thermometer used?
A thermometer is a tool that measures temperature — how hot or cold something is. Thermometers are used to see if you have a fever or tell you how cold it is outside. … Doctors use thermometers to check your body temperature — a very high or low body temperature means you’re sick.
Is mercury thermometer banned in India?
In accordance with the Minamata Convention on Mercury IMA has decided to request all its members to phase out Mercury containing BP Instruments and Thermometer by 27th December 2016. Mercury is one of the most toxic natural elements.
Do red thermometers have mercury?
How can I tell if my thermometer has mercury? Mercury is a silver-white to gray substance. If your thermometer is filled with a red liquid your thermometer contains red dyed alcohol or mineral spirits and not mercury. These are safer alternatives to mercury fever thermometers.
Can you touch mercury?
Mercury is a very toxic or poisonous substance that people can be exposed to in several ways. If it is swallowed like from a broken thermometer it mostly passes through your body and very little is absorbed. If you touch it a small amount may pass through your skin but not usually enough to harm you.
What is mercury used for?
Which thermometer does not use mercury?
Answer: Digital Thermometer are available which do not use mercury.
What is an example of mercury?
An example of mercury is the silver-white metal inside of a thermometer that is liquid at room temperature. A silvery-white poisonous metallic element liquid at room temperature and used in thermometers barometers vapor lamps and batteries and in the preparation of chemical pesticides.
What can replace mercury?
Why is water not used in thermometer?
Water is not able to be used as a thermometer liquid because of its higher freezing point and lower boiling point than the other liquids in general. … This range is very negligible as compared to other liquids like mercury which has a freezing point of about −39∘C and boiling point 356∘C.
Who invented mercury thermometer?
Is mercury thermometer accurate?
Is mercury still used?
Most uses have been discontinued. Some medicines use small amounts of these compounds as preservatives. Learn about the use of thimerosal a mercury-containing preservative in vaccines. In addition mercury is still used in skin lighteners and anti-aging products for the skin.
What is the blue liquid in a thermometer?
The science and development of non-mercury thermometers have made great improvements over the past few years. The blue spirit thermometers listed contain non-toxic isoamyl benzoate and dye. These thermometers can be stored horizontally their separation rate is equal to or better than mercury thermometers.
What is the red liquid in a thermometer called?
Can mercury thermometer show wrong temperature?
Many people think it inaccurate mainly because they use the instruments in the wrong way. There are too many factors affecting the forehead temperature including room temperature skin dryness and more. The measurements you get after you wash face or use an ice bag can not reflect the right body temperature.
What are the 4 types of thermometers?
- Digital thermometers. …
- Ear (or tympanic) thermometers. …
- Infared thermometers. …
- Strip-type thermometers. …
- Mercury thermometers.
How do thermometers work without mercury?
Spirit thermometers use a non-toxic alcohol instead of mercury to register the temperature. … Digital thermometers contain a device called a thermoresistor. The thermoresistor has an electrical current running through it and the resistance or how freely the current can flow changes with temperature.
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Science Behind It | Why mercury is used in thermometer ?| in English | by Er.Sir
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why Mercury is used in thermometer?