- #1
con31773
- 6
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Calculate the change in entropy of the Universe as a result of the following
operations:
(a) A copper block of mass 0.4kg and thermal capacity 150JK-1 at 100◦C is
placed in a lake at 10◦C.
dS=dQ/T dQ=mCdT
Tried simply combining these equations and integrating to find change of entropy of block. Knowing that final temperature of the block will be approximately the initial temperature of the lake. So we get
mc[ln(T)] between boundaries of T1 and T2. However, this thermal capacity does not have the standard units for c, which is JK-1Kg-1, so I am questioning my whole approach. Assuming this is just some typo perhaps and I do indeed do this, I am not sure on how to find the universal entropy change. Any help would be greatly appreciated.
Many thanks in advance.
operations:
(a) A copper block of mass 0.4kg and thermal capacity 150JK-1 at 100◦C is
placed in a lake at 10◦C.
dS=dQ/T dQ=mCdT
Tried simply combining these equations and integrating to find change of entropy of block. Knowing that final temperature of the block will be approximately the initial temperature of the lake. So we get
mc[ln(T)] between boundaries of T1 and T2. However, this thermal capacity does not have the standard units for c, which is JK-1Kg-1, so I am questioning my whole approach. Assuming this is just some typo perhaps and I do indeed do this, I am not sure on how to find the universal entropy change. Any help would be greatly appreciated.
Many thanks in advance.