ࡱ > q` b/ bjbjqPqP 42 : : \ ^ ^ ^ ^ ^ ^ ^ \ $ D Z Z Z Z 5 5 5 0 2 2 2 2 2 2 $ h " l V ] ^ a 5 5 a a V ^ ^ Z Z a ^ Z ^ Z 0 a 0 V @ ^ ^ $ Z 8 В-f 3 R 4 0 0 " . " $ " ^ $ 5 v T D C 5 5 5 V V 5 5 5 a a a a $ r ^ ^ ^ ^ ^ ^ THERMODYNAMICS OF SYNTHESIS OF p- AND d-ELEMENT OXIDES by proceeding from these hydroxides: Unnoticed peculiarities O.V. Mikhailov, R.A. Yusupov, N.I. Naumkina Kazan State Technological University, Kazan, Russia. E-mail: HYPERLINK "mailto:ovm@kstu.ru" ovm@kstu.ru With thermodynamic point of view, the question about of obtaining of oxides of a series metals (M) MO and M2O3 types from corresponding hydroxides M(OH)2 8 M ( O H ) 3 . h a s b e e n c o n s i d e r e d . I t h a s b e e n n o t e d t h a t , a l t h o u g h i n t h e m a n y c a s e s p r o c e s s e s M ( O H ) 2 ( c r ) ! M O ( c r ) + H 2 O ( l i q ) , M ( O H ) 2 ( c r ) ! M O ( c r ) + H 2 O ( g a s ) , M ( O H ) 3 ( c r ) ! ( 1 / 2 ) M 2 O 3 ( c r ) + ( 3 / 2 ) H 2 O ( l i q ) 8 M ( O H ) 3 ( c r ) ! ( 1 / 2 ) M 2 O 3 ( c r ) + ( 3 / 2 ) H 2 O ( g a s ) h a v e b e e n t h e r m o d y n a m i c a l l y f o r b i d d e n u n d e r s t a n d a r d c o n d i t i o n s ( DG 0 > 0 ) , n e v e r t h e l e s s , f o r m a t i o n o f M O a n d M 2 O 3 f r o m M ( O H ) 2 a n d M ( O H ) 3 i n a l k a l i n e m e d i u m ( p H > 1 2 ) i s o b s e r v e d a t r o o m t e m p e r a t u r e . T h e d e p e n d e n c e s DG ( T ) = DH 0 T DS 0 o f a n u m b e r o f M ( I I ) ( M n O , F e O , CoO, NiO, CuO, ZnO, CdO, SnO, PbO) and M(III) oxides (Al2O3, Cr2O3, Y2O3, In2O3, Au2O3, Tl2O3, Bi2O3) and experimental data ascribing given process of formation of Mn(II), Fe(II), Ni(II), Cu(II), Zn(II), Pb(II), Fe(III), Al(III), Cr(III) oxides have been presented. The example of such data for oxides of lead(II) have been shown lower. C, mol(l1 pHThe dependence of residual concentrations of Pb(II) ions on pH in the Pb(II) OH system a t T = 2 9 8 K . 1 r e g i o n o f f o r m a t i o n o f y e l l o w f o r m P b O , 2 r e g i o n o f f o r m a t i o n o f y e l l o w - g r e e n f o r m P b O , 3 - r e g i o n o f f o r m a t i o n o f g a r n e t - r e d f o r m P b O . ;O D>@<8@>20=8O P b O ( y e l l o w f o r m ) DG ( T ) = 1 0 . 9 0 . 0 2 6 7 T ( T : = 1 3 5 . 0 >!) DG ( T ) = 5 4 . 9 0 . 1 4 5 3 T & ' n o t u v w x z y j h4 h- UmH sH h- h- h4 h- mH sH h4 h- 5mH sH h- h- 5mH sH h4 h- 5>*mH sH h- h- 5>*mH sH "h4 h- 5;@NH mH sH h4 h- 56@mH sH h4 h- 5;@mH sH + 7 t u R ^ ` 6 8 ~ "( $( r( ( $d, $If a$gd- d, $If gd- d, $If gdWo $hd, `ha$gd- 8 d, gd- $a$gd- $d, a$gd- b/ o q r t u w z { | } ~ j n ~ w h&~ h&~ NH mH sH h&~ h- h&~ h- H*mH sH h&~ h- 5mH sH h&~ h- mH sH h&~ h&~ mH sH h- h- >*h- h- h- h- 0J h4 h- 0J mH sH j h4 h- UmH sH #j h4 h- UmH sH . & ( * , 2 4 8 : B D F H L N \ ^ ` b d f h l n h&~ h- h&~ h- 5mH sH h&~ h- mH sH h&~ h&~ H*mH sH h&~ h- H*mH sH O n r t v x & 8 > @ B v z ¶ܝܑёёё܆ynn h`k h- mH sH h`k h&~ NH mH sH h`k h&~ mH sH h&~ h- 5mH sH h&~ h&~ NH mH sH h&~ h- H*mH sH h&~ h- 6mH sH h&~ h- OJ QJ mH sH h&~ h- mH sH h&~ h&~ mH sH h&~ h- H*mH sH h&~ h&~ H*mH sH * ! 6 8 9 : ; ? @ A B E F G H L M N O S T U V Z [ \ ] a b c d f i j Ǽ haR mH sH h`k h`k NH mH sH h`k h- H*mH sH h`k h`k mH sH h`k h2]) mH sH h`k h- mH sH h`k h- 5H*mH sH h`k h- 5mH sH h`k h- 56mH sH h`k h- 5OJ QJ mH sH 4 # - . 5 : O Q R S T Y Z [ ] ^ _ ` ygWLA hWo h- mH sH j hWo hWo UhWo h- 5CJ aJ mH sH "hWo hWo 5CJ H*aJ mH sH % j hWo hWo 5CJ aJ mH sH hWo hWo 5CJ aJ mH sH "hE hWo 56CJ aJ mH sH h`k h- B*mH ph sH ha4c mH sH h;p mH sH h`k h`k NH mH sH h`k h`k mH sH hq( mH sH h`k h- mH sH haR mH sH ` " $ @ B j t v x z ʻʻʻʻʻʻʻʻʊʻʻ{j{^{ hj CJ aJ mH sH hj hj CJ NH aJ mH sH hj hj CJ aJ mH sH hj h