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Why must I use kelvin temperature when working with gases rather than Celsius?
Wiki User
∙ 16y ago
See the Related Questions link to the left of this answer: "Why must you always use Kelvins when dealing with the ideal gas law?" Also, our understanding of gases is based on the kinetic theory of gases. This theory has to with understanding how fast gases move as a function of temperature. Since molecular motion stops at 0 K, everything is referenced to the kelvin scale, which is an absolute measurement of temperature. Celsius is just referenced to the freezing point and boiling point of water, which really has nothing to do with most gases!
Wiki User
∙ 16y ago
Wiki User
∙ 16y agoThe short answer: Because that's how it works! The reason it works that way is that the kelvin scale is reference to absolute zero. This is the lowest possible temperature possible. In contrast, both the Celsius and Fahrenheit scales are referenced to other things. Just to give an example of why using degrees Celsius won't work in the ideal gas law. You can gave a negative temperature in Celsius. Using PV = nRT, you would get a negative value for either P, V, or n. You can't have a negative volume, pressure or number of moles, can you?!
Wiki User
∙ 15y agoThis may or may not answer your question, but it may help you find the answer: Thermal energy is proportional to the kelvin scale. e.g. a gas at 40K has double the amount of energy compared to a gas at 20K. however, this is not true for other scales of temperature, take for example, the Celsius scale; at 40oC a gas does not have double the energy it has at 20oC. This is because 20oC is 293K and 40oC is 313K, and it is obvious that 313K is not double 293K. Also, thinking about it, the kelvin scale starts from absolute zero and cannot have have a negative value, hence making more mathematical sense when it is fed into an equation.
Wiki User
∙ 11y agobecause you will end up having to change the units a lot. Such as going from Celsius to kelvins. However the more important is the pressure. Switching from ATM to mm Hg or Torr, Pascals or Kilo-pascals The units will always be thrown at you variously.
Wiki User
∙ 14y agoKelvin is commonly used in chemistry to take out the pesky negative. Its one less thing to be worried about. Gasses like Helium with a very low boiling point, -200 some degrees Celsius, can be expressed as kelvin as a degree such as 80 degrees kelvin, rather then -200 some degrees Celsius. it's not a must, its more of a convenience.
Wiki User
∙ 9y agoAll gas calculations involve using the Kelvin scale because Kelvin begins to measure at absolute zero. The absolute zero measure is the only one in which there is 0 heat.
Wiki User
∙ 13y agobefore doing problems we have to convert units into their standrad form to get a standrad answer otherwise there is a chance of mistake.Secondly gas laws are only applicable at kelvin scale.
Wiki User
∙ 10y agoTheoretically, a gas can never reach zero or a negative temp and always gives positive numbers
Wiki User
∙ 11y agoyes
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Why does the percent error calculation have to be performed in celsius rather than kelvin?
That is just utter nonsense. Kelvin is the absolute scale so percentages should be calculated in Kelvin and not Celsius.
What is the temperature scale preferred for gas calculations?
Kelvin is the temperature scaled preferred by scientists for doing pretty much everything rather than deciding to wear a coat or a bathing suit (though given the outside temperature in Kelvin it wouldn't take most of them long to make that determination either).
Why is the SI unit of temperature Kelvin but not Celsius?
Celsius and Fahrenheit are relative scales which are compared with freezing and boiling points of water. While kelvin is not relative and is an absolute scale. From graphical representation of Charles's when one extrapolate the graph straight, it will touch the zero volume at -273.16 Celsius or OK. This OK is the start or emergence of kelvin scale which is not related to anything, but absolute.
Melting point of ice in kelvin?
The diamond has no melting point. The triple point for carbon is about 11 MPa and about 4600 K. Rather than melting, carbon sublimes at about 3900 K.
Is 7 Celsius warmer than 1 Celsius?
Yes. Or, rather, less cold.
Why does the percent error calculation have to be performed in celsius rather than kelvin?
That is just utter nonsense. Kelvin is the absolute scale so percentages should be calculated in Kelvin and not Celsius.
Why is the kelvin scale used rather than the celsius scale?
Because the Kelvin scale is an absolute scale. In the context of thermodynamics, 2 K is twice as "hot" as 1 K. And 3 K is three times as "hot". That is not true of the Celsius or Fahrenheit (or other temperature) scales.
What scale boils water at 373 degree's?
Firstly, temperatures measured in Kelvin (K) are not degrees but rather, just numbers. However, 373 K is the same as 100 degrees C. At that temperature, pure water begins to boil at sea level.
How do you use kelvin scale?
The Kelvin scale measures temperature. You can use it the same way you would use the Fahrenheit scale or the Celsius scale, but it also has an additional use. Since the Kelvin scale starts at the true zero of temperature, when there is no random thermal motion, rather than starting at some arbitrary point such as the freezing point of water (Celsius) or the coldest temperature that was obtainable in the laboratory at the time the Fahrenheit scale was first devised, you can make much more meaningful comparisons in Kelvin. If something has twice the temperature in Kelvin than something else has, then it actually is twice as hot. That is not true of other temperature scales. 20oC is not twice as hot as 10oC. But 20oK actually is twice as hot as 10oK.
Why do scientists use the Kelvin and Celsius scale rather than the Fahrenheit scale?
Celsius is a very accurate measurement between the freezing and boiling points of water. 0 being freezing, and 100 boiling. Kelvin is the measurement of absolute zero, where particles stop moving altogether. Kelvin has the same conversion rating, only 0 Kelvin is -273 degrees Celsius. The Kelvin scale is an absolute scale. This means that 2 K is twice as hot as 1 K and so on. Neither the Celsius nor the Fahrenheit scales do that. The Centigrade (or Celsius scale are based on the freezing and boiling points of water (at normal pressure), the Fahrenheit scale was not: the 0 was the lowest temperature attained by ice and salt.
What does it mean to say that the specific heat capacity of water is greater than that of iron?
Heat capacity is the amount of heat needed to increase the temperature of an element (a given mass) by a temperature unit.Specific Heat Capacity is the amount of heat in Joulesneeded to heat 1kg of an element by 1 degree Kelvin.Joules per Kilogram KelvinIf the SHC of water is higher than that of iron, it means, you need more heat to increase the temperature of 1kg of water in 1 degree Celsius, than the heat you need to increase the temperature in 1 degree Celsius of the same mass of iron.P.S.A Celsius temperature difference is the same as a Kelvin temperature difference. In measuring SHC, we only need to focus on temperature difference rather than the temperature value. Add 273.15 to the Celsius measurement of the temperature to get the Kelvin temperature value.
What temperature scale must always be used when working gas law problems?
PV = nRT You can use whatever you want essentially, however S.I units are generally preferred so you don't end up in a mess. P in pascals (Pa) V in metres (m3) n is just the number of moles R is the gas constant 8.3145x103 (JK-1mol-1) T is temperature in Kelvin (K) Converting Celsius to Kelvin is simple (degrees celcius + 273.15) = temperature in Kelvin Note:- if you keep pressure in Torr rather than Pa, you have to use a different value for the gas constant R.
What is the formula for converting celsius to Kelvin?
Celsius and Kelvin scales use the same size unit or "degree." But Kelvin has its zero point at absolute zero rather than the freezing point of water. Absolute zero (zero K) is about -273.15° Celsius.To convert Celsius to Kelvin, add 273.15. For example 100° C is 373.15 kelvins.To convert kelvins to Celsius, subtract 273.15. For very large numbers, such as 5000 K, the value (4726.85° C) is not going to be that different.
What is the temperature scale preferred for gas calculations?
Kelvin is the temperature scaled preferred by scientists for doing pretty much everything rather than deciding to wear a coat or a bathing suit (though given the outside temperature in Kelvin it wouldn't take most of them long to make that determination either).
Which group of people most often use Kelvin scale?
Yes, the Kelvin scale is very widely used in the sciences because it provides an absolute temperature scale as opposed to the relative scales like Celsius and Fahrenheit. In the world of cryogenics, particularly that of the really low temperatures, those nearer absolute zero, we see the Kelvin scale used frequently. To cite a single example, it is easier to talk about the boiling point of helium being 4.22 K rather than −268.93 °C, or −452.07 °F.
What does 225 K mean as a temperature reading?
The Kelvin scale uses the same degree size as Celsius, but starts 273.15 degrees lower, at absolute zero (in Celsius zero is the freezing point of water). So Kevin temperatures have a numerical value greater by 273.15. 225 K would therefore indicate a rather cold temperature of about -48.15° C (-54.67°F).
What is a temperature reading of 237 Kelvins equivalent to?
The Kelvin scale uses the same degree size as Celsius, but starts 273.15 degrees lower, at absolute zero (in Celsius zero is the freezing point of water). So Kevin temperatures have a numerical value greater by 273.15. 237 K would therefore indicate a rather cold temperature of about -36.15° C (-33.07°F).
