作者hurryken (考不上怎麼半 T T)
看板TransBioChem
標題Re: [普化] 台大87
時間Sat Jul 9 01:12:44 2005
※ 引述《ayabbe (芮妮齊薇格)》之銘言:
: ※ 引述《Sophina (真)》之銘言:
: : 17.from the values given for △H and △S at 298K,which of the following
: : reactions are spontaneous under standard condition at 298K?
: : (a)2PbS(s)+3O2(g)→2PbO(s)+O2(g) △H=-844kJ △S=-165J/K
: : (b)2POCl3(g)→2PCl3(g)+O2(g) △H=572kJ △S=179J/K
: : (c)N2(g)+3F2(g)→2NF3(g) △H=-249kJ △S=-278J/K
: : (d)N2(g)+3Cl2(g)→2NCl3(g) △H=460kJ △S=-275J/K
: : (e)N2F4(g)→2NF2(g) △H=85kJ △S=198J/K
: : 謝謝^^
: (依題目來說, A,E 自發)
: according free energy happened function, if G wants spontaneous...
: (delta省略) (can spon = + , can't spon = -)
: H>0 H<0 H>0 H<0
: G = H - T*S S>0 S<0 S<0 S>0
: in high Temp + - - +
: in low Temp - + - + ( 不知道我有沒寫對)
這個可以這樣記
G = H - T S
- - + (-跟-)
+ + - (所以+就跟+)
↑ + + (↑是高溫自發 +跟+所以↑)
↓ - - (所以反過來-跟-就是↓)
我絕得還挺好季的 至少推出來很easy
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 220.132.177.148