Difference between a kelvin and a celcius degree

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Homework Statement


I feel stupid posting this but I am completely lost. This is a problem on my Chemistry textbook's website, which gives immediate feedback on whether you are right or wrong, and I am just unable to get it right.

The question:
What is the difference between a kelvin and a Celsius degree?

Below in the answer box it says :
1 K = _________ °C

The Attempt at a Solution


So to convert from K to °C you do temperature in K - 273.15, right? So I did 1 - 273.15 and got -272.15. I put that in as my answer and got it wrong.

I feel like I am doing it right, so I'm not sure if maybe the answer key is wrong. Or maybe I am just stupid. I've tried numerous other numbers and keep getting it wrong, and for each wrong answer I am getting points off. Please help.

Thanks
 
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So you are confused about which way to go.
Think about the degrees this way: 0 C is 273.15 K. I agree with YOUR answer. Absolute Zero K would be -273.15 C. One degree up from absolute zero, same size degree regardless of scale chosen between K or C, would then be -273.15+1=-272.15 C
 
I think the problem is probably asking about the magnitude of a Kelvin degree as compared to the magnitude of a Celsius degree. Since they are the same magnitude, it wants the answer that 1K = 1C. Try this and see if this is the right answer.
 
phyzguy said:
I think the problem is probably asking about the magnitude of a Kelvin degree as compared to the magnitude of a Celsius degree. Since they are the same magnitude, it wants the answer that 1K = 1C. Try this and see if this is the right answer.

It was right! Thanks so much. I'm a bit confused by the answer though. Does 1K = 1C because of the fact that a change in 1 degree in both K and C is the same amount? Also, how am I supposed to know that they want 1K = 1C rather than 1K = -272.15?
 
asdf12321asdf said:
It was right! Thanks so much. I'm a bit confused by the answer though. Does 1K = 1C because of the fact that a change in 1 degree in both K and C is the same amount? Also, how am I supposed to know that they want 1K = 1C rather than 1K = -272.15?

Yes, that's right, the point is that a change of 1K is the same as a change of 1C. As far as how you're supposed to know what they are asking, I have no idea. Maybe you should point out to your teacher that the problem is ambiguous.
 
phyzguy said:
Yes, that's right, the point is that a change of 1K is the same as a change of 1C. As far as how you're supposed to know what they are asking, I have no idea. Maybe you should point out to your teacher that the problem is ambiguous.

Ok, will do. Thanks again for the help!
 
asdf12321asdf said:
What is the difference between a kelvin and a Celsius degree?

phyzguy said:
Maybe you should point out to your teacher that the problem is ambiguous.

They don't ask about TEMPERATURE, they ask about a DEGREE. I don't see ambiguity here, even if I understand the confusion - but confusion comes from the lack of understanding of the difference between unit used and quantity measured.