The ice bath test is the easiest way to test a thermometer for accuracy, assuming your thermometer will display temperatures of 32°F or less. The advantage of this method is that an accurate thermometer will always read 32°F in a properly made ice bath regardless of altitude or atmospheric pressure.
What is the most accurate form of thermometer?
Digital thermometers are the most accurate way to measure body temperature. There are many types, including oral, rectal, and forehead, plus many that are multifunctional.
What is the accuracy of lab thermometer?
For example, a NIST Traceable® thermometer may state the range as -50ºC to +70 ºC and will have an accuracy of ± 1 ºC. A NIST Certified thermometer may state that it is certified at five temperatures with correction factors and tested at 0 ºC (ice point), assuring very accurate measurements.
Why is mercury a good choice for thermometer?
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. Mercury thermometers are used in households, laboratory experiments, and industrial applications.
Why do different thermometers give different readings?
“Liquid in glass thermometers show different readings for temperatures other than the fixed points because of differing expansion properties. A thermometer which uses a gas gives the same readings regardless of which gas is used”.
What is the least accurate method for taking a temperature Why?
Temperatures taken from the armpit are usually the least accurate. For older children and adults, oral readings are usually accurate — as long as the mouth is closed while the thermometer is in place.
What are the 4 types of thermometers?
- Digital thermometers.
- Ear (or tympanic) thermometers.
- Infared thermometers.
- Strip-type thermometers.
- Mercury thermometers.
Which thermometer is best digital or mercury?
A digital thermometer is simple and convenient to use. It gives faster results than a mercury thermometer which usually takes time to heat up. It is safer as it doesn’t contain any harmful chemicals. It gives more precise results than a mercury thermometer.
Which thermometer is used in laboratory?
Thermocouple Thermometer These devices are used for the quick measurement of temperature. It finds its application in laboratories.
How accurate are liquid thermometers?
They are available in standard, dampened movement, and silicone-filled types. Generally, these thermometers offer ±1% full-scale accuracy.
Is mercury thermometer more accurate?
But mercury thermometers also have real advantages over the alternatives. They’re often cheaper and more accurate, especially at higher temperatures. And unlike one common alternative, electronic thermometers, they’re self-contained (no wires sticking out) and require no power.
Why mercury is used in thermometer rather than water?
Liquid Mercury has a very low vapor pressure than water. So it will be more sensitive than water to the changes in the atmospheric pressure and ups faster to store the changes. Mercury is used in thermometers because it has high coefficient of thermal expansion.
Why is alcohol used in thermometer?
The alcohol thermometer is an alternative to the mercury-in-glass thermometer and has similar functions. Unlike mercury, alcohol is less toxic and will evaporate away quickly if subjected to high temperatures. Therefore, it is used to measure low temperatures.
Why is water not used in thermometer?
Water cannot be used in thermometer because of its higher freezing point and lower boiling point than other liquids . If water is used in a thermometer , it will start phase change at 0oC and 100oC and will not measure temperature , out of this range .
Why is my thermometer not consistent?
Differences between measurements can also result from the following factors: The thermometer is not the same temperature as the room you are measuring in (Example: it has been in a much warmer or colder room). The thermometer is inserted into the ear canal at a different depth or angle.
Can a thermometer give a false high reading?
Yes, a thermometer can give you a false reading even if you follow all instructions. At the height of the pandemic, thermometers were flying off the shelves.
What is the most accurate method to measure body temperature Why?
In general, rectal temperatures are considered to be more accurate when checking for fever in a young child. Plastic strip thermometers measure skin temperature, not body temperature. They are not recommended for general home use.
What is the most accurate method for taking a temperature why quizlet?
What is the most accurate method for taking temperature, why? The most accurate method is rectal since it is an internal measurement.
What are the 7 types of thermometer?
- Digital thermometers. Digital thermometers are regarded as the fastest and most accurate type of thermometer.
- Electronic ear thermometers.
- Forehead thermometers.
- Plastic strip thermometers.
- Pacifier thermometer.
- Glass and mercury thermometers.
How do you read a laboratory thermometer?
Which is more accurate oral or armpit temperature?
An armpit (axillary) temperature is usually 0.3°C (0.5°F) to 0.6°C (1°F) lower than an oral temperature. A forehead (temporal) scanner is usually 0.3°C (0.5°F) to 0.6°C (1°F) lower than an oral temperature.
What are the disadvantages of digital thermometer?
- Digital thermometers have the disadvantage of having dead batteries.
- Submerging a conventional thermometer in warm, soapy water is simple, but doing it with a digital thermometer is more complicated.
- Some digital thermometers are more accurate than others.
Which is more accurate digital or analog thermometer?
An analog thermometer is much harder to read forcing you to squint your eyes at the tube and make an estimate. These thermometers are only capable of measuring within one degree Celsius. Digital thermometers are more accurate, allowing temperature to be measured within .
Why mercury is not used in digital thermometer?
Mercury is a toxic substance and is very difficult to dispose if a thermometer breaks. Moreover digital thermometers are easier to read than mercury thermometers. The accuracy of both the thermometers are nearly same.
What is a thermometer used for in chemistry?
Thermometers measure temperature by using materials that expand or contract when heated or cooled. Mercury or alcohol thermometers, for example, have a reservoir of liquid that expands when heated and contracts when cooled, so the liquid column lengthens or shortens as the temperature of the liquid changes.