作者reckson1017 (GOD)
看板Chemistry
标题Re: 请问一题关於热力学的问题
时间Thu Feb 9 00:52:49 2006
※ 引述《GOPOL (爬不起来阿!!)》之铭言：
: in the plot of enthalpy VS temperature for metals A and B
: if the slope of A less than B which of the following is true
: (A)the entropy of A is less than B
: (B)melting point of metal A is higher than that of metal B
: (C)more heat is needed to heat up metal B than A when the equal
: moles of A and B are used
: (D)heat will flow from B to A when they are in direct contact
: 请化学高手指教一下 这一题不太懂
气体
定容状态
dU=TdS-PdV
dS=dU/T+ P/T dV
dS=Cv/T dT + R/V dV
因为题目是金属
定压
dH=TdS+VdP
dS=dH/T -V/TdP
dS=Cp/T dT-R/P dP
考虑斜率 H&T关系
dH/dT=CpdT/dT=Cp
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1F：推 AppleAmily:有必要扯那麽多公式吗 @_@ 02/09 14:17
2F：→ shok:对阿 热力学除了背一堆公式来解以外 还有其他好方法吗？ 02/09 22:00
3F：推 reckson1017:题目有提到的都写出来 新手最好一眼就会懂 02/10 00:18