- It cannot measure very low temperature, because its freezing point is high (-40oC)
- Mercury is poisonous, so it harmful if its tube is broken.
- Its price is very high.
- display is harder to read.
- cannot be used for thermograph.
- slow response.
- fragile.
What is the disadvantage of using mercury in thermometer?
Disadvantages of Mercury:
It cannot measure very low temperature
, because its freezing point is high (-40oC) Mercury is poisonous, so it harmful if its tube is broken. Its price is very high.
What are the advantages and disadvantages of mercury as a working fluid?
-It is
a good conductor of heat
and therefore the whole liquid reaches the temperature of the surroundings quickly. -It does not wet (cling to the sides of) the tube. -It expands uniformly (linear expansion) and responds quickly to temperature changes, hence is sensitive. -It has a visible meniscus.
What are the advantages and disadvantages of mercury and alcohol?
| Advantages Disadvantages | lower freezing point (-114 0C ) less durable (alcohol evaporates) | larger coefficient of expansion alcohol can polymerise | less hazardous fluid loss by evaporation hard to avoid | lower boiling point (60 0C ) |
|---|
What are the advantages and disadvantages of mercury?
| advantages disadvantages | Mercury thermometer | cheap display is harder to read | durable does not work below -39�C (Hg freezing pount) | accurate cannot be used for thermograph |
|---|
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.
What are the advantages of using mercury?
- It is opaque and shining. …
- It does not wet the glass.
- It has a low freezing point and a high boiling point. …
- It is a good conductor of hest, so it quickly absorbs heat to attain the temperature of the object.
- It has a wide range of temperature expansion.
Which thermometer is better mercury or alcohol?
It is
more durable than alcohol thermometer
because mercury does not evaporate easily. It is smaller in size as compared to alcohol one. Mercury does not wet the wall of the thermometer, which means that results can be highly accurate.
Why is alcohol used in thermometers instead of mercury?
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.
Which thermometer is most sensitive?
By exploiting the difference between the speed of two different beams of colored light when traveling through a heated crystalline disk,
University of Adelaide researchers
claim to have produced the world’s most sensitive thermometer – with an accuracy of 30 billionths of a degree.
Why was the mercury steam cycle abandoned commercially?
The mercury cycle offers an efficiency increase compared to a steam-only cycle because energy can be injected into the Rankine cycle at higher temperature. Metallurgical developments have
allowed steam-only plants to increase in efficiency over time
, making the mercury vapour turbine obsolete.
What are the advantage of the use of mercury in a 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.
Does a thermometer have mercury?
In a mercury thermometer,
a glass tube is filled with mercury
and a standard temperature scale is marked on the tube. … Mercury thermometers can be used to determine body, liquid, and vapor temperature. Mercury thermometers are used in households, laboratory experiments, and industrial applications.
Is mercury thermometer more accurate than infrared?
The median difference between infrared tympanic and rectal mercury thermometry in the whole material was -0.5 degree C, but increased to -1.4 degrees C in a selected group with rectal temperature 38 degrees C or more. … In a clinical setting the infrared ear thermometer has a very low sensitivity for detecting fever.
What is the boiling point of mercury?
The element’s atomic mass is 200.59 grams per mole and its specific gravity is 13.5 times that of water. Mercury has a melting point of -38.9
o
C, a boiling point of
356.7
o
C
, and is the only metal to remain in liquid form at room temperature.
What are liquid in glass thermometers?
A LiG thermometer, by definition, is a glass capillary tube with a liquid-filled bulb at one end. … The liquid that is contained within the thermometer may be one of many different substances, but the most common are
mercury, toluene (or a similar organic substance)
, and low-hazard biodegradable liquids.
