How to Convert Heat Capacity Equation Units to British Engineering System?

AI Thread Summary
The discussion focuses on converting the heat capacity equation from metric to British engineering units. The original equation is expressed in Joules per kmol per Kelvin, and participants suggest converting Joules to BTUs and temperatures from Kelvin to Fahrenheit. Key conversion factors include 1 Joule equaling approximately 0.000947817 BTU and the temperature conversion from Kelvin to Fahrenheit. There is also mention of the importance of dividing by molar weight to achieve the correct units of BTU per lbm per °F. The conversation emphasizes the utility of dimensional analysis for these conversions.
Rizwan Yaseen
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How we change the units of Heat capacity equation to British engineering system
Cp=2. 657*10^4 +42. 37T - 1. 425*10^-2T^2
 
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Hello Rizwan, :welcome:

You don't mention any units in your expression. Can I guess it's for ice at 0 C and expressed in J per kmol per Kelvin ?

I don't think the British units system managed to mess up the kmol too, so all you have to do is convert Joules to British dingdongs, so e.g.
if 1 Joule is 0.000947817 BTU,
and 1 K is 9/5 F (+ some constant) multiply by 0.000947817 and divide by 9/5. That's all.

But if you want to mangle it further, you still have to divide by the molar weight to get ##\approx## 0.5 BTU/lbm/F

PS why do I have to google that for you? You can find such conversions all over the place !
 
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BvU said:
Hello Rizwan, :welcome:

You don't mention any units in your expression. Can I guess it's for ice at 0 C and expressed in J per kmol per Kelvin ?

I don't think the British units system managed to mess up the kmol too, so all you have to do is convert Joules to British dingdongs, so e.g.
if 1 Joule is 0.000947817 BTU,
and 1 K is 9/5 F (+ some constant) multiply by 0.000947817 and divide by 9/5. That's all.

But if you want to mangle it further, you still have to divide by the molar weight to get ##\approx## 0.5 BTU/lbm/F

PS why do I have to google that for you? You can find such conversions all over the place !
 
Yes units are J/kgmol/Δ K and T in °K and convert them to BTU/kgmol/ΔF and expressT In °F (degree F)
 
I know this might probably be too late, but you can always use dimensional analysis. Then constants would then begin to appear and you can distribute them afterwards.
 
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Rizwan Yaseen said:
Yes units are J/kgmol/Δ K and T in °K and convert them to BTU/kgmol/ΔF and expressT In °F (degree F)
Are you sure you don't mean lb-moles?
 
Oops sorry sir but it's lb moles I write in a hurry but still this conversion confuse Me How I might get this one.
 
1 Joule = ? BTU

1 kg = ? lb

1 kg-mole = ? lb-moles

1 degree centigrade = ?? degrees F

Fill in the ??s
 
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