物理化學(xué)電子教案第六章化學(xué)平衡-資料下載頁
2025-02-18 12:44本頁面
【正文】 反應(yīng)。例如： ( 1 ) A B C D( 2) C E F H? ? ?? ? ? 利用 值很負(fù)的反應(yīng)，將 值負(fù)值絕對值較小甚至略大于零的反應(yīng)帶動起來。 rmG? $rmG? $?上一內(nèi)容 ?下一內(nèi)容 ?回主目錄 耦合反應(yīng)的用途： 例如：在 K時(shí)： 12 2 4 2 r m ,1 ( 1) T iO ( s) 2Cl ( g) T iC l ( l ) O ( g) 1 4 kJ m ol G? ? ? ? ? ?$反應(yīng) (1)、 (2)耦合，使反應(yīng) (3)得以順利進(jìn)行。 12 2 r m ,2( 2) C( s) O ( g) C O ( g) 394 .38 kJ m olG? ? ? ? ? ?$1r m2 2 4 2,3 ( 3) T iO ( s) C ( s) 2C l ( g) T iC l ( l ) C O ( g) 4 kJ m ol G ????????則$?上一內(nèi)容 ?下一內(nèi)容 ?回主目錄 近似計(jì)算 1． 的估算 rm()GT? $r( 5 K )T ?rrr m r m r mr m r m rr m r m r( ) ( ) ( )( ) ( ) d( ) ( ) dTpTTpTG T H T T S TH T H T C TCS T S T TT? ? ? ? ?? ? ? ? ??? ? ? ???$ $ $$$$$當(dāng) 不大，或不要作精確計(jì)算時(shí)，設(shè) ，則： pC 0pC??r m r m r r m r( ) ( ) ( ) G T H T T S T a bT? ? ? ? ? ??$ $ $ 這里實(shí)際上設(shè)焓和熵變化值與溫度無關(guān)，從 K的表值求出任意溫度時(shí)的 值。 rmG? $?上一內(nèi)容 ?下一內(nèi)容 ?回主目錄 近似計(jì)算 2．估計(jì)反應(yīng)的有利溫度 r m r m r m( ) ( ) ( )G T H T T S T? ? ? ? ?$ $ $ 通常焓變與熵變在化學(xué)反應(yīng)中的符號是相同的。要使反應(yīng)順利進(jìn)行，則 越小越好。 rm()GT? $ r m r m( 1 ) ( ) 0 , ( ) 0H T S T? ? ? ?$$提高溫度對反應(yīng)有利。 r m r m( 2 ) ( ) 0 , ( ) 0H T S T? ? ? ?降低溫度對反應(yīng)有利。 ?上一內(nèi)容 ?下一內(nèi)容 ?回主目錄 轉(zhuǎn)折溫度 通常將 時(shí)的溫度稱為轉(zhuǎn)折溫度，意味著反應(yīng)方向的變化。這個(gè)溫度可以用 K時(shí)的 和 值進(jìn)行近似估算。 rm ( ) 0GT??$rmH? $S? $r m rr m r()(()HTTST???轉(zhuǎn)折）$$?上一內(nèi)容 ?下一內(nèi)容 ?回主目錄 JACOBUS HENRICUS VAN’ T HOFF JACOBUS HENRICUS VAN’ T HOFF (18521911) Dutch physical chemist,received the first Nobel Prize in chemistry in 1901 for “ the discovery of the laws of chemical dynamics and of osmotic pressure.” Van’ t Hoff was one of the early developers of the laws of chemical kiics,developing mehtods for determining the order of a reaction。he deduced the relation between temperature and the equilbrium constant of a chemical reaction. ?上一內(nèi)容 ?下一內(nèi)容 ?回主目錄 JACOBUS HENRICUS VAN’ T HOFF In 1874, van’ t Hoff (and also . Le Bel, independently) proposed what must be considered one of the most important ideas in the history of chemistry, namely the tetrahedral carbon bond. Van’ t Hoff carried Pasteur’ s ideas on asymmetry to the molecular level , and asymmetry required bonds tetrahedrally distributed about a central carbon atom. Structural anic chemistry was born. ?上一內(nèi)容 ?下一內(nèi)容 ?回主目錄 JOHN DALTON JOHN DALTON (17661844) English chemist, physicist, and meteorologist, is considered by many to be the “ father of the atomic theory of matter,although grandfather is perhaps a more he suffered. In 1803, he published his paper “ Absorption of Gases by Water and Other Liquids,” in which he presented what is now known as Dalton’ s law of partial pressures. ?上一內(nèi)容 ?下一內(nèi)容 ?回主目錄 JOHN DALTON He was led to his theory of atomism by his studies of gases. In one of his papers published in 1805, he said, “ Why does not water admit its bulk of every kind of gas alike?…The circumstance depends on the weight and number of the ultimate particles of the several gases.” John Dalton was led to the atom by reflecting that different gases had different values of the Henry’ s law constant. ?上一內(nèi)容 ?下一內(nèi)容 ?回主目錄 謝謝觀看 /歡迎下載 BY FAITH I MEAN A VISION OF GOOD ONE CHERISHES AND THE ENTHUSIASM THAT PUSHES ONE TO SEEK ITS FULFILLMENT REGARDLESS OF OBSTACLES. BY FAITH I BY FAITH
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