作者reckson1017 (GOD)
看板Chemistry
標題Re: 請問一題關於熱力學的問題
時間Thu Feb 9 00:52:49 2006
※ 引述《GOPOL (爬不起來阿!!)》之銘言：
: 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
: 請化學高手指教一下 這一題不太懂
氣體
定容狀態
dU=TdS-PdV
dS=dU/T+ P/T dV
dS=Cv/T dT + R/V dV
因為題目是金屬
定壓
dH=TdS+VdP
dS=dH/T -V/TdP
dS=Cp/T dT-R/P dP
考慮斜率 H&T關係
dH/dT=CpdT/dT=Cp
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 203.67.78.143
1F：推 AppleAmily:有必要扯那麼多公式嗎 @_@ 02/09 14:17
2F：→ shok:對阿 熱力學除了背一堆公式來解以外 還有其他好方法嗎？ 02/09 22:00
3F：推 reckson1017:題目有提到的都寫出來 新手最好一眼就會懂 02/10 00:18