Celcius vs Kelvin for T1 and T2
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Celcius vs Kelvin for T1 and T2
Do we need to be aware of any technical changes to the formula if we decide to use Kelvins vs Celcius in the calculations for temperature in both T1 and T2? Or should we just stick with Kelvin to be safe?
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Re: Celcius vs Kelvin for T1 and T2
I say stick to Kelvin because that is typically what we use. Plus in most equations, the gas constant is in the equation which is 8.314 J/(K * mol).
Re: Celcius vs Kelvin for T1 and T2
Always use kelvin. You won’t get the right answer if you use Celsius
Re: Celcius vs Kelvin for T1 and T2
Always always always use Kelvin. Most standard konstants that we use are set for Kelvin, as well -- and I wouldn't suggest that you use the R values (for example) that use Celsius.
Re: Celcius vs Kelvin for T1 and T2
I think it's safe to always use Kelvin unless told otherwise. Chemistry pretty much prefers Kelvin over other temperatures.
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Re: Celcius vs Kelvin for T1 and T2
Kelvin is most likely going to be the correct unit, so I would convert to K first.
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Re: Celcius vs Kelvin for T1 and T2
I'd say your best bet is to always convert to Kelvin. I don't think you get the correct answer with Celsius.
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Re: Celcius vs Kelvin for T1 and T2
You should use Kelvin and not Celcius since the R constant is in terms of K.
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Re: Celcius vs Kelvin for T1 and T2
I always use Kelvin because I dont want to risk getting the incorrect answer using celsius.
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Re: Celcius vs Kelvin for T1 and T2
Some problems it's okay to use Celsius, but it's good to get into the habit of using Kelvin. Most of the time, using Celsius will give the wrong answer. To be sure, make sure you write out your units and double check that they cancel out correctly.
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Re: Celcius vs Kelvin for T1 and T2
I use Kelvin all the time because if you need to use the gas constant somewhere in the problem it won't work with Celsius.
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Re: Celcius vs Kelvin for T1 and T2
You should always use Kelvin unless the question explicitly states to use Celsius.
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Re: Celcius vs Kelvin for T1 and T2
You generally stick to Kelvin but there was a sapling question that asked for the answer in terms of Celsius, so just make sure you double check to see what the question is actually asking for.
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Re: Celcius vs Kelvin for T1 and T2
I usually always convert to Kelvin because most of our constants use Kelvin. Unless a constant given specifically uses Celsius or the question asks you to use/give your answer in Celsius, just use Kelvin.
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Re: Celcius vs Kelvin for T1 and T2
I say stick to Kelvin since most of the constants we use are in Kelvin!
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Re: Celcius vs Kelvin for T1 and T2
I would stick with kelvin as in order to cancel temperature in our formula the gas constants usually have kelvin as the denominator.
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Re: Celcius vs Kelvin for T1 and T2
For this formula, Kelvin. A good rule of thumb whenever wondering what units of temperature to use in general is to look at the units of the constants you are using. For example, specific heat can sometimes be in Celsius while R is usually in Kelvin.
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Re: Celcius vs Kelvin for T1 and T2
For this formula, I would stick to Kelvin. I think it is useful to convert to units that match any constants in the formula. This makes it easier to avoid mistakes with units in your final answer too.
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Re: Celcius vs Kelvin for T1 and T2
For this formula, you should always convert celsius to kelvin. I have often made that mistake in the past and have got a question wrong, So make sure you convert your temperatures to kelvin.
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Re: Celcius vs Kelvin for T1 and T2
Since the formula does not indicate a change in temperature, you cannot interchange Celsius and Kelvin. Therefore, you would have to only use Kelvins in this case because the units cancel out with the gas constant, R.
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Re: Celcius vs Kelvin for T1 and T2
For that specific formula, I would definitely use Kelvin! This is because you're looking at the ratio of T2/T1, and so the ratio would be different if you're using ˚C versus Kelvin.
For things that are asking for the change in temperature, such as q=mC∆T, that's when you can use either ˚C or Kelvin, since the same in temperature will be the same with either ˚C or Kelvin (from ˚C+273.15=K). Otherwise, especially when you have to do ratios, use Kelvin units. Hope this helped!
For things that are asking for the change in temperature, such as q=mC∆T, that's when you can use either ˚C or Kelvin, since the same in temperature will be the same with either ˚C or Kelvin (from ˚C+273.15=K). Otherwise, especially when you have to do ratios, use Kelvin units. Hope this helped!
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Re: Celcius vs Kelvin for T1 and T2
You would have to use Kelvin only, since the units of Kelvin need to cancel out with the gas constant R, as well as how it's not interchangeable since it's not a "change" in temperature but rather the two temperatures itself.
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Re: Celcius vs Kelvin for T1 and T2
The usage of kelvin or celsius will depend on the other units of the other values in the equation. You would want them all to match, so only use kelvin, if the other values also include kelvin units and vice versa for celsius.
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Re: Celcius vs Kelvin for T1 and T2
Are there ever any problems where we could end up with a wrong answer if we use Kelvin?
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Re: Celcius vs Kelvin for T1 and T2
unless the value for temperature is a change in temperature (ie ∆T as in the equation q=mC∆T), then it matters whether you use K or Celcius. For most equations that use a value of R, temperature must be in Kelvin, so a safe bet would be to convert to Kelvin however it is always important to look at the units of the other values/constants when deciding. Again, C and K are only interchangeable when talking about change in temperature, in all other cases you must determine the appropriate units.
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Re: Celcius vs Kelvin for T1 and T2
It is always better to use Kelvin since it is the SI unit for temperature. Also, since R is units of J/mol*K, you want to use Kelvin so that the units cancel out.
Re: Celcius vs Kelvin for T1 and T2
You should use Kelvin for most calculations, including this one!
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Re: Celcius vs Kelvin for T1 and T2
Possibly using kelvin will be the most reliable answer instead of celsius. If you are given celsius, simply convert to kelvin by adding 273. It is also important to remember to use the proper units for the R constant.
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Re: Celcius vs Kelvin for T1 and T2
I usually use Kelvin and if the problem gives me temperature in Celsius then I just convert.
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Re: Celcius vs Kelvin for T1 and T2
You should use Kelvin in the van't Hoff equation. If you forget just look at the units in the gas constant which are given in kelvin.
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Re: Celcius vs Kelvin for T1 and T2
It depends on which constant you're using. Typically the constant is R = 8.314 J/ Kxmol, so you would have to use Kelvins in that case.
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Re: Celcius vs Kelvin for T1 and T2
Sometimes I found that I don't need to convert to Kelvins in order to get the right answer. Just make sure that your units are consistent. It's always good to write down the units in your equations.
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Re: Celcius vs Kelvin for T1 and T2
I believe using Kelvin is the safe option. But I know at time it's okay to use Celsius because both units have the same degree of change.
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Re: Celcius vs Kelvin for T1 and T2
The safest bet is to always use Kelvin. That being said, if you are finding the difference between T1 and T2 (such as when calculating heat absorbed or released using mcΔT), it will not matter which one you use.
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Re: Celcius vs Kelvin for T1 and T2
it depends on the unit of ideal gas number or specific heat capacity
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Re: Celcius vs Kelvin for T1 and T2
Hi,
A good rule of thumb is always use Kelvin for your thermodynamic equations. In MOST (not all) cases, we have to use Kelvins because the constants we are given (such as the ideal gas constant) are expressed in terms of Kelvin (this ensures it cancels out for your final answer).
Hope this helps! :)
A good rule of thumb is always use Kelvin for your thermodynamic equations. In MOST (not all) cases, we have to use Kelvins because the constants we are given (such as the ideal gas constant) are expressed in terms of Kelvin (this ensures it cancels out for your final answer).
Hope this helps! :)
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Re: Celcius vs Kelvin for T1 and T2
personally, i use kelvin as a default for almost every equation we have to use.
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Re: Celcius vs Kelvin for T1 and T2
I would use Kelvin depending on the units of the problem, for example, if you have to use the ideal gas constant (8.3145 J K^-1*mol^-1) then use Kelvin. However, if you are doing a problem where you use q = m*c*delta T, the delta T is the same whether you have Celsius or kelvin so you can keep your temperature in Celsius.
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Re: Celcius vs Kelvin for T1 and T2
I would be sure to convert to Kelvin if temperature in given in Celsius because K is the standard unit and is used in most equations involving temperature. However, as someone above mentioned, the unit shouldn't matter if you are using delta T, or the difference in temperature, because the difference should be the same regardless of the units.
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Re: Celcius vs Kelvin for T1 and T2
You should be using kelvin for T1 and T2. If you ever forget which one to use, I advise writing all of your units out for each variable in the equation and making sure they all cross out in the end leaving you only with the desired unit(s) for the problem.
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Re: Celcius vs Kelvin for T1 and T2
Hi! I always stick to kelvin since most constants use K. It doesn't hurt to spend the few extra seconds to convert!
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Re: Celcius vs Kelvin for T1 and T2
I prefer staying with Kelvin mainly because most of the units involved in calculations include Kelvin rather than Celsius.
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Re: Celcius vs Kelvin for T1 and T2
From experience I think it's safe to always use Kelvin unless told otherwise. It is a simple step but can be easily forgotten.
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Re: Celcius vs Kelvin for T1 and T2
I'm pretty sure you are supposed to always use Kelvin for this class.
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Re: Celcius vs Kelvin for T1 and T2
I believe you should be using temp in Kelvin if using 8.341 for R constant.
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Re: Celcius vs Kelvin for T1 and T2
It would be the safest option to just stick with Kelvin unless it specifically says otherwise.
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Re: Celcius vs Kelvin for T1 and T2
Stick with Kelvin! But make sure the units of the gas constant you use are the same.
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Re: Celcius vs Kelvin for T1 and T2
Bryce Ramirez 1J wrote:Do we need to be aware of any technical changes to the formula if we decide to use Kelvins vs Celcius in the calculations for temperature in both T1 and T2? Or should we just stick with Kelvin to be safe?
Hi! I think that it is the most safe to use Kelvin but always try to check if there are any units that suggest you would need to use Celsius. Also, when subtracting temperatures it does not matter what unit you are using because it will always be the same difference. Hope this helps!
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Re: Celcius vs Kelvin for T1 and T2
Usually we should use kelvin for temperature (especially for the Van Hoff equation) but for thermo in general, you have to pay attention to the units of other things you are using to solve the problem. For example, the specific heat capacity of liquid water is 4.184 J/g degrees C so you would use celsius for delta T (even though technically delta T would be the same for Kelvin and Celsius). Just pay attention to the units of other things you are using.
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Re: Celcius vs Kelvin for T1 and T2
Stick to Kelvin when using equations. This is especially true when using the natural log function in our formulas as you will receive a wrong answer if using celsius.
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Re: Celcius vs Kelvin for T1 and T2
You should stick with kelvin because most of the common/most used constants in this class use kelvin.
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Re: Celcius vs Kelvin for T1 and T2
i think kelvin is a safer choice, since all the formulas were created using kelvin basically. using celsius would cause an issue with the units not matching up, and you would have to switch all other components that are related to temperature from kelvin to celsius. that sounds like a lot of extra work
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Re: Celcius vs Kelvin for T1 and T2
Is there any condition in thermodynamics where we should use Celcius over kelvin in an equation?
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Re: Celcius vs Kelvin for T1 and T2
I believe our answers should always be in kelvin, unless celsius is specifically asked, the formulas always use kelvin though
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Re: Celcius vs Kelvin for T1 and T2
I believe that we should always have temperature in units of Kelvin since using Celsius might give you issues with your answer and units, so unless the question directly asks for the units to be in celsius, just stick to using Kelvin.
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Re: Celcius vs Kelvin for T1 and T2
Using Kelvin for calculation is better as the units cancel out in most circumstances when using Kelvin. There are some circumstances where it asks for the difference in temperature or Delta T and in that circumstance Kelvin and Celsius are the same. It is still better to use Kelvin though.
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Re: Celcius vs Kelvin for T1 and T2
I recommend you to use Kelvin only. If the question asks for celsius, then convert it!
Re: Celcius vs Kelvin for T1 and T2
In most thermodynamic calculations referencing delta G, H, or S, kelvins are used. Thus, for Tl and T2 calculations, kelvins should be optimized.
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Re: Celcius vs Kelvin for T1 and T2
Use Kelvin. But definitely make sure to look at which units are being given and make sure that they are being converted to the right units
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Re: Celcius vs Kelvin for T1 and T2
I would probably use kelvin just to look safe and to make sure there are no small technical errors
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Re: Celcius vs Kelvin for T1 and T2
We should usually use Kelvin, and you can remember this by seeing the units of R.
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Re: Celcius vs Kelvin for T1 and T2
For basically all calculations in chemistry we use kelvin! if the problem you are solving requires delta t it is okay to use celsius to calculate change in temperature because the units of change for celsius and kelvin are the same, kelvin is jsut 273 values greater.
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Re: Celcius vs Kelvin for T1 and T2
I think Kelvin should be used, unless the problem states otherwise
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Re: Celcius vs Kelvin for T1 and T2
Make sure to use Kelvin, since you want to make sure the units cancel out. The units of the gas constant are J*mol^-1*K, so you have to convert the temperature to Kelvin to solve the problem.
Re: Celcius vs Kelvin for T1 and T2
Typically, always use Kelvin in calculations. The only case you can use Celsius is whether it is specified in the answer/units or when there is a change in temperature, since a degree in celsius = a degree in kelvin.
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Re: Celcius vs Kelvin for T1 and T2
Rule of thumb is the always use Kelvins, but pay attention to units! For example, if you're using a heat capacity value that has celsius in its units, then use celsius. If your looking for deltaT, it doesn't really matter because you are just looking for the difference between Tfinal and Tinitial, which would be the same for both Kelvins and celsius. With that said, a lot of times constants related to thermodynamics (like R, the gas constant), have Kelvins in their units--so use kelvins so that it'll match!
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Re: Celcius vs Kelvin for T1 and T2
I would always convert to Kelvin, unless it is specifically told in units of Celsius!
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