ij»¯Ñ§Ð¡×éÀûÓÃÏÂͼװÖÃÍê³ÉFe2O3 ºÍCOµÄ·´Ó¦£®

£¨1£©ÊµÑ鿪ʼǰ£¬Ê×ÏȱØÐë½øÐеIJÙ×÷Ϊ______£®ÊµÑ鿪ʼʱ£¬Í¨ÈëCOÆøÌåºÍ¼ÓÈȵÄÏȺó˳ÐòΪ______£¬µãȼ¾Æ¾«µÆ֮ǰ£¬±ØÐë¼ìÑé´Ó×°ÖÃÖÐÅųöµÄCOµÄ´¿¶È£®ÊµÑé¹ý³ÌÖУ¬ÅжϷ´Ó¦·¢ÉúµÄÏÖÏóΪ______£®
£¨2£©ÊµÑéʱ¿ÉÔھƾ«µÆ»ðÑæÉÏÕÖÒ»¸ö½ðÊôÍøÕÖ£¬¸Ã½ðÊôÍøÕÖµÄ×÷ÓÃÊÇ______¡¢______£®ÈôÒªÌá¸ß·´Ó¦Î¶ȣ¬»¹¿ÉÑ¡ÓõļÓÈÈÒÇÆ÷Ϊ______£®
£¨3£©²éÔÄ×ÊÁÏÖª£¬Fe2O3ºÍCO½øÐмÓÈÈ·´Ó¦£¬¹ÌÌåÖÊÁ¿Ó뷴ӦζȵĹØϵÈçÏÂͼËùʾ£®

ÏÖ²âµÃ¾Æ¾«µÆ¶ÔFe2O3¼ÓÈÈζȿɴﵽ500¡æ¡«600¡æ£¬Ôò¸ÃζÈÏ£¬Fe2O3 µÄ»¹Ô­²úÎïÊÇ______£®ÇëÉè¼ÆÒ»¸ö¼òµ¥µÄʵÑ飬֤Ã÷650¡æ¡«700¡æʱFe2O3µÄ»¹Ô­²úÎ¼òÊöʵÑé²Ù×÷ºÍÏÖÏó______£®¿É¹©Ñ¡ÔñµÄÊÔ¼Á£ºÏ¡H2SO4¡¢Ï¡ÑÎËá¡¢KMnO4ÈÜÒº¡¢NaOHÈÜÒº¡¢KSCNÈÜÒº£®
¡¾´ð°¸¡¿·ÖÎö£º£¨1£©ÒòCOÄÜȼÉÕ£¬µãȼ²»´¿µÄCOÄÜÒýÆð±¬Õ¨£¬COÄÜ»¹Ô­Ñõ»¯ÌúÉú³ÉÌúºÍ¶þÑõ»¯Ì¼£»
£¨2£©¾Æ¾«µÆ»ðÑæÉÏÕÖÒ»¸ö½ðÊôÍøÕÖ£¬Äܼ¯ÖлðÑ棬Ìá¸ßζȣ¬¿ÉÀûÓþƾ«ÅçµÆ´úÌæ¾Æ¾«µÆ£»
£¨3£©CO»¹Ô­Ñõ»¯ÌúµÄ»¹Ô­²úÎïΪ¿ÉÄÜFe3O4£¬FeOºÍFe£®Fe2O3¼ÓÈÈζȿɴﵽ500¡æ¡«600¡æ£¬ÖÊÁ¿ÓÉ46.4g¼õÉÙΪ45g£¬»¹Ô­²úÎïΪFe3O4£»650¡æ¡«700¡æʱ£¬ÖÊÁ¿ÓÉ43.2g¼õÉٽϴ󣬻¹Ô­²úÎïΪFeO£¬ÀûÓÃÑÇÌúÀë×ӵĻ¹Ô­ÐÔÀ´Éè¼ÆʵÑ飮
½â´ð£º½â£º£¨1£©ÒòCOÄÜȼÉÕ£¬µãȼ²»´¿µÄCOÄÜÒýÆð±¬Õ¨£¬COÄÜ»¹Ô­Ñõ»¯ÌúÉú³ÉÌúºÍ¶þÑõ»¯Ì¼£¬ÔòʵÑéʱӦÏȼì²é×°ÖõÄÆøÃÜÐÔ£¬ÊµÑéʱÏÈͨÈëCOÒ»¶Îʱ¼ä£¬Åųö×°ÖÃÖеĿÕÆø£¬ºó¼ÓÈÈ£»µ±¹Û²ìµ½ºì×ØÉ«·ÛÄ©Öð½¥±äºÚ£¬³ÎÇåʯ»ÒË®±ä»ë×Ç£¬ËµÃ÷COÓëÑõ»¯Ìú·´Ó¦Éú³ÉÌúºÍ¶þÑõ»¯Ì¼£¬
¹Ê´ð°¸Îª£º¼ì²é×°ÖõÄÆøÃÜÐÔ£»ÏÈͨÈëCOÒ»¶Îʱ¼ä£¬ºó¼ÓÈÈ£»ºì×ØÉ«·ÛÄ©Öð½¥±äºÚ£¬³ÎÇåʯ»ÒË®±ä»ë×Ç£»
£¨2£©¾Æ¾«µÆ»ðÑæÉÏÕÖÒ»¸ö½ðÊôÍøÕÖ£¬Äܼ¯ÖлðÑ棬Ìá¸ß·´Ó¦Î¶ȣ¬È·±£ÊÜÈȾùÔÈ£¬ÊµÑéÖпÉÀûÓþƾ«ÅçµÆ´úÌæ¾Æ¾«µÆ£¬
¹Ê´ð°¸Îª£ºÌá¸ß·´Ó¦Î¶ȣ¬È·±£ÊÜÈȾùÔÈ£»¾Æ¾«ÅçµÆ£»
£¨3£©CO»¹Ô­Ñõ»¯ÌúµÄ»¹Ô­²úÎïΪ¿ÉÄÜFe3O4£¬FeOºÍFe£®Fe2O3¼ÓÈÈζȿɴﵽ500¡æ¡«600¡æ£¬ÖÊÁ¿ÓÉ46.4g¼õÉÙΪ45g£¬»¹Ô­²úÎïΪFe3O4£»650¡æ¡«700¡æʱ£¬ÖÊÁ¿ÓÉ43.2g¼õÉٽϴ󣬻¹Ô­²úÎïΪFeO£¬ÎªÑéÖ¤»¹Ô­²úÎÔÚÊÊÁ¿´ý¼ìÎïÖмÓÈëÏ¡H2SO4ÖÁÍêÈ«Èܽ⣬ÔÙ¼ÓÈëÉÙÁ¿¸ßÃÌËá¼ØÈÜÒº£¬ÈÜÒº×ÏÉ«ÍÊÈ¥£¬¿É˵Ã÷»¹Ô­²úÎïΪFeO£¬
¹Ê´ð°¸Îª£ºFe3O4£»ÔÚÊÊÁ¿´ý¼ìÎïÖмÓÈëÏ¡H2SO4ÖÁÍêÈ«Èܽ⣬ÔÙ¼ÓÈëÉÙÁ¿¸ßÃÌËá¼ØÈÜÒº£¬ÈÜÒº×ÏÉ«ÍÊÈ¥£®
µãÆÀ£º±¾Ì⿼²éÖƱ¸ÊµÑé·½°¸µÄÉè¼Æ£¬Ã÷È·COµÄ¿ÉȼÐÔ¡¢»¹Ô­ÐÔ¼°·¢ÉúµÄ»¯Ñ§·´Ó¦Êǽâ´ð±¾ÌâµÄ¹Ø¼ü£¬×¢Ò⣨3£©ÖÐͼÏóµÄ·ÖÎö¼°Êý¾Ý·ÖÎöÅжϻ¹Ô­²úÎïΪ½â´ðµÄÄѵ㣬ÌâÄ¿ÄѶȽϴó£®
Á·Ï°²áϵÁдð°¸
Ïà¹ØÏ°Ìâ

¿ÆÄ¿£º¸ßÖл¯Ñ§ À´Ô´£º ÌâÐÍ£º

ijÑо¿ÐÔѧϰС×éÀûÓÃÏÂͼËùʾװÖÃÑо¿ÒÒ´¼ÓëÑõ»¯ÌúµÄ·´Ó¦£¬Çë»Ø´ðÏÂÁÐÎÊÌ⣺

£¨1£©×°ÖÃÖÐÊÔ¹ÜBµÄ×÷ÓÃÊÇ
·ÀÖ¹µ¹Îü
·ÀÖ¹µ¹Îü
£®
£¨2£©ÊµÑéÖпɹ۲쵽ʯӢ¹ÜAÖеÄÏÖÏóΪ
×ó²à¹ÌÌåÓɺì×ØÉ«Öð½¥±äΪºÚÉ«£¬ÓÒ²à°×É«·ÛÄ©±äΪÀ¶É«
×ó²à¹ÌÌåÓɺì×ØÉ«Öð½¥±äΪºÚÉ«£¬ÓÒ²à°×É«·ÛÄ©±äΪÀ¶É«
£®
£¨3£©·´Ó¦Í£Ö¹ºó£¬È¡³öÊÔ¹ÜCÔھƾ«µÆÉϼÓÈÈÖÁ·ÐÌÚ£¬¿É¹Û²ìµ½ÓкìÉ«³Áµí²úÉú£®Ð´³ö¸Ã·´Ó¦µÄ»¯Ñ§·½³Ìʽ
CH3CHO+2Cu£¨OH£©2
¡÷
CH3COOH+Cu2O+2H2O
CH3CHO+2Cu£¨OH£©2
¡÷
CH3COOH+Cu2O+2H2O
£®
£¨4£©ÎªÁ˲ⶨ·´Ó¦ºóʯӢ¹ÜA×ó²à¹ÌÌåÖÐÌúÔªËصĺ¬Á¿£¬½øÐÐÈçÏÂʵÑ飺

£¨ i£©²½Öè¢ÛÖÐÓõ½µÄ²£Á§ÒÇÆ÷ÓÐÉÕ±­¡¢²£Á§°ô¡¢½ºÍ·µÎ¹Ü¡¢
250mlµÄÈÝÁ¿Æ¿
250mlµÄÈÝÁ¿Æ¿
£®
£¨ ii£©ÏÂÁÐÓйز½Öè¢ÜµÄ²Ù×÷ÖÐ˵·¨ÕýÈ·µÄÊÇ
ce
ce
£®
a£®µÎ¶¨¹ý³ÌÖпÉÀûÓõí·ÛÈÜÒº×÷Ϊָʾ¼Á
b£®µÎ¶¨¹ÜÓÃÕôÁóˮϴµÓºó¿ÉÒÔÖ±½Ó×°Òº
c£®×¶ÐÎÆ¿²»ÐèÒªÓôý²âÒ¹ÈóÏ´
d£®µÎ¶¨¹ý³ÌÖУ¬ÑÛ¾¦×¢Êӵζ¨¹ÜÖÐÒºÃæ±ä»¯
e£®µÎ¶¨½áÊøºó£¬30sÄÚÈÜÒº²»»Ö¸´Ô­À´µÄÑÕÉ«£¬ÔÙ¶ÁÊý
£¨iii£©ÓÉ¿òͼÖÐÊý¾Ý¼ÆË㣬¿ÉµÃʯӢ¹ÜA×ó²à¹ÌÌåÖÐÌúÔªËصİٷֺ¬Á¿Îª
77.78%
77.78%
£®

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖл¯Ñ§ À´Ô´£º ÌâÐÍ£º

£¨13·Ö£©Ä³Ñо¿ÐÔѧϰС×éÀûÓÃÏÂͼËùʾװÖÃÑо¿ÒÒ´¼ÓëÑõ»¯ÌúµÄ·´Ó¦£¬Çë»Ø´ðÏÂÁÐÎÊÌ⣺

£¨1£©×°ÖÃÖÐÊÔ¹ÜBµÄ×÷ÓÃÊÇ                            ¡£

£¨2£©ÊµÑéÖпɹ۲쵽ʯӢ¹ÜAÖеÄÏÖÏóΪ                            ¡£

£¨3£©·´Ó¦Í£Ö¹ºó£¬È¡³öÊÔ¹ÜCÔھƾ«µÆÉϼÓÈÈÖÁ·ÐÌÚ£¬¿É¹Û²ìµ½ÓкìÉ«³Áµí²úÉú¡£Ð´³ö¸Ã·´Ó¦µÄ»¯Ñ§·½³Ìʽ                             ¡£

£¨4£©ÎªÁ˲ⶨ·´Ó¦ºóʯӢ¹ÜA×ó²à¹ÌÌåÖÐÌúÔªËصĺ¬Á¿£¬½øÐÐÈçÏÂʵÑ飺

£¨i£© ²½Öè¢ÛÖÐÓõ½µÄ²£Á§ÒÇÆ÷ÓÐÉÕ±­¡¢²£Á§°ô¡¢½ºÍ·µÎ¹Ü¡¢                  ¡£

£¨ii£©ÏÂÁÐÓйز½Öè¢ÜµÄ²Ù×÷ÖÐ˵·¨ÕýÈ·µÄÊÇ                          ¡£

a£®µÎ¶¨¹ÜÓÃÕôÁóˮϴµÓºó¿ÉÒÔÖ±½Ó×°Òº

b£®×¶ÐÎÆ¿²»ÐèÒªÓôý²âÒ¹ÈóÏ´

c£®µÎ¶¨¹ý³ÌÖУ¬ÑÛ¾¦×¢Êӵζ¨¹ÜÖÐÒºÃæ±ä»¯

d£®µÎ¶¨½áÊøºó£¬30 sÄÚÈÜÒº²»»Ö¸´Ô­À´µÄÑÕÉ«£¬ÔÙ¶ÁÊý

£¨iii£©ÓÉ¿òͼÖÐÊý¾Ý¼ÆË㣬¿ÉµÃʯӢ¹ÜA×ó²à¹ÌÌåÖÐÌúÔªËصİٷֺ¬Á¿Îª       ¡£

 

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖл¯Ñ§ À´Ô´£º ÌâÐÍ£º

£¨15·Ö£©Ä³Ñо¿ÐÔѧϰС×éÀûÓÃÏÂͼËùʾװÖÃÑо¿ÒÒ´¼ÓëÑõ»¯ÌúµÄ·´Ó¦£¬Çë»Ø´ðÏÂÁÐÎÊÌ⣺

£¨1£©×°ÖÃÖÐÊÔ¹ÜBµÄ×÷ÓÃÊÇ                            ¡£

£¨2£©ÊµÑéÖпɹ۲쵽ʯӢ¹ÜAÖеÄÏÖÏóΪ                                   ¡£

£¨3£©·´Ó¦Í£Ö¹ºó£¬È¡³öÊÔ¹ÜCÔھƾ«µÆÉϼÓÈÈÖÁ·ÐÌÚ£¬¿É¹Û²ìµ½ÓкìÉ«³Áµí²úÉú¡£Ð´³ö¸Ã·´Ó¦µÄ»¯Ñ§·½³Ìʽ                                ¡£

£¨4£©ÎªÁ˲ⶨ·´Ó¦ºóʯӢ¹ÜA×ó²à¹ÌÌåÖÐÌúÔªËصĺ¬Á¿£¬½øÐÐÈçÏÂʵÑ飺

£¨i£© ²½Öè¢ÛÖÐÓõ½µÄ²£Á§ÒÇÆ÷ÓÐÉÕ±­¡¢²£Á§°ô¡¢½ºÍ·µÎ¹Ü¡¢                  ¡£

£¨ii£©ÏÂÁÐÓйز½Öè¢ÜµÄ²Ù×÷ÖÐ˵·¨ÕýÈ·µÄÊÇ                          ¡£

a£®µÎ¶¨¹ý³ÌÖпÉÀûÓõí·ÛÈÜÒº×÷Ϊָʾ¼Á

b£®µÎ¶¨¹ÜÓÃÕôÁóˮϴµÓºó¿ÉÒÔÖ±½Ó×°Òº

c£®×¶ÐÎÆ¿²»ÐèÒªÓôý²âÒ¹ÈóÏ´

d£®µÎ¶¨¹ý³ÌÖУ¬ÑÛ¾¦×¢Êӵζ¨¹ÜÖÐÒºÃæ±ä»¯

e£®µÎ¶¨½áÊøºó£¬30 sÄÚÈÜÒº²»»Ö¸´Ô­À´µÄÑÕÉ«£¬ÔÙ¶ÁÊý

£¨iii£©ÓÉ¿òͼÖÐÊý¾Ý¼ÆË㣬¿ÉµÃʯӢ¹ÜA×ó²à¹ÌÌåÖÐÌúÔªËصİٷֺ¬Á¿Îª       ¡£

 

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖл¯Ñ§ À´Ô´£º ÌâÐÍ£ºÔĶÁÀí½â

£¨14·Ö£©¢ñ.ÏÂÁÐʵÑé²Ù×÷»ò¶ÔʵÑéÊÂʵµÄÃèÊöÕýÈ·µÄÊÇ            £¨ÌîÐòºÅ£©

¢Ù ʵÑéÊÒÅäÖÆÂÈ»¯ÑÇÌúÈÜҺʱ£¬½«ÂÈ»¯ÑÇÌúÏÈÈܽâÔÚÑÎËáÖУ¬È»ºóÓÃÕôÁóˮϡÊͲ¢¼ÓÈëÉÙÁ¿Ìú·Û£»

¢Ú ÅäÖÆÒ»¶¨Å¨¶ÈµÄÈÜҺʱ£¬¸©ÊÓÈÝÁ¿Æ¿µÄ¿Ì¶ÈÏߣ¬»áʹÅäÖƵÄŨ¶ÈÆ«¸ß£»ÊµÑéÊҲⶨÖкÍÈÈʱ£¬¹ýÔç¶ÁÊý»áʹ²â¶¨½á¹ûÆ«µÍ£»

¢Û ÊÔ¹ÜÖмÓÈëÉÙÁ¿µí·Û£¬ÔÙ¼ÓÈëÒ»¶¨Á¿Ï¡ÁòËᣬ¼ÓÈÈ3£­4·ÖÖÓ£¬È»ºó¼ÓÈëÒø°±ÈÜÒº£¬Æ¬¿Ìºó¹Ü±ÚÉÏÓС°Òø¾µ¡±³öÏÖ

¢Ü ·Ö±ðÏòÌå»ýºÍpH¾ùÏàͬµÄÑÎËáºÍ´×ËáÖеμӵÈŨ¶ÈµÄÇâÑõ»¯ÄÆÈÜÒº£¬ÍêÈ«ÖкÍʱÏûºÄµÄÇâÑõ»¯ÄÆÈÜÒºµÄÌå»ýÒ»Ñù¶à

¢Ý ÏòNaOHÈÜÒº¡¢KSCNÈÜÒº¡¢·ÐÌÚµÄÕôÁóË®ÖзֱðµÎ¼Ó±¥ºÍµÄFeCl3ÈÜÒºµÃµ½µÄ·ÖɢϵÒÀ´ÎΪ£º×ÇÒº¡¢ÈÜÒº¡¢½ºÌå

¢ò.ijÑо¿ÐÔѧϰС×éÀûÓÃÏÂͼËùʾװÖÃÑо¿ÒÒ´¼ÓëÑõ»¯ÌúµÄ·´Ó¦£¬Çë»Ø´ðÏÂÁÐÎÊÌ⣺

£¨1£©×°ÖÃÖÐÊÔ¹ÜBµÄ×÷ÓÃÊÇ                            ¡£

£¨2£©ÊµÑéÖпɹ۲쵽ʯӢ¹ÜAÖеÄÏÖÏóΪ                               ¡£

£¨3£©·´Ó¦Í£Ö¹ºó£¬È¡³öÊÔ¹ÜCÔھƾ«µÆÉϼÓÈÈÖÁ·ÐÌÚ£¬¿É¹Û²ìµ½ÓкìÉ«³Áµí²úÉú¡£Ð´³ö¸Ã·´Ó¦µÄ»¯Ñ§·½³Ìʽ                                ¡£

£¨4£©ÎªÁ˲ⶨ·´Ó¦ºóʯӢ¹ÜA×ó²à¹ÌÌåÖÐÌúÔªËصĺ¬Á¿£¬½øÐÐÈçÏÂʵÑ飺

£¨i£©²½Öè¢ÛÖÐÓõ½µÄ²£Á§ÒÇÆ÷ÓÐÉÕ±­¡¢²£Á§°ô¡¢½ºÍ·µÎ¹Ü¡¢                  ¡£

£¨ii£©ÏÂÁÐÓйز½Öè¢ÜµÄ²Ù×÷ÖÐ˵·¨ÕýÈ·µÄÊÇ                          ¡£

a£®µÎ¶¨¹ý³ÌÖпÉÀûÓõí·ÛÈÜÒº×÷Ϊָʾ¼Á

b£®µÎ¶¨¹ÜÓÃÕôÁóˮϴµÓºó¿ÉÒÔÖ±½Ó×°Òº

c£®×¶ÐÎÆ¿²»ÐèÒªÓôý²âÒ¹ÈóÏ´

d£®µÎ¶¨¹ý³ÌÖУ¬ÑÛ¾¦×¢Êӵζ¨¹ÜÖÐÒºÃæ±ä»¯

e£®µÎ¶¨½áÊøºó£¬30 sÄÚÈÜÒº²»»Ö¸´Ô­À´µÄÑÕÉ«£¬ÔÙ¶ÁÊý

£¨iii£©ÓÉ¿òͼÖÐÊý¾Ý¼ÆË㣬¿ÉµÃʯӢ¹ÜA×ó²à¹ÌÌåÖÐÌúÔªËصİٷֺ¬Á¿Îª       ¡£

 

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖл¯Ñ§ À´Ô´£º2010-2011ѧÄêÖØÇìÊиßÈýÏÂѧÆÚµÚÒ»´ÎÔ¿¼£¨Àí×Û£©»¯Ñ§²¿·Ö ÌâÐÍ£ºÊµÑéÌâ

£¨13·Ö£©Ä³Ñо¿ÐÔѧϰС×éÀûÓÃÏÂͼËùʾװÖÃÑо¿ÒÒ´¼ÓëÑõ»¯ÌúµÄ·´Ó¦£¬Çë»Ø´ðÏÂÁÐÎÊÌ⣺

£¨1£©×°ÖÃÖÐÊÔ¹ÜBµÄ×÷ÓÃÊÇ                             ¡£

£¨2£©ÊµÑéÖпɹ۲쵽ʯӢ¹ÜAÖеÄÏÖÏóΪ                            ¡£

£¨3£©·´Ó¦Í£Ö¹ºó£¬È¡³öÊÔ¹ÜCÔھƾ«µÆÉϼÓÈÈÖÁ·ÐÌÚ£¬¿É¹Û²ìµ½ÓкìÉ«³Áµí²úÉú¡£Ð´³ö¸Ã·´Ó¦µÄ»¯Ñ§·½³Ìʽ                              ¡£

£¨4£©ÎªÁ˲ⶨ·´Ó¦ºóʯӢ¹ÜA×ó²à¹ÌÌåÖÐÌúÔªËصĺ¬Á¿£¬½øÐÐÈçÏÂʵÑ飺

£¨i£© ²½Öè¢ÛÖÐÓõ½µÄ²£Á§ÒÇÆ÷ÓÐÉÕ±­¡¢²£Á§°ô¡¢½ºÍ·µÎ¹Ü¡¢                   ¡£

£¨ii£©ÏÂÁÐÓйز½Öè¢ÜµÄ²Ù×÷ÖÐ˵·¨ÕýÈ·µÄÊÇ                           ¡£

a£®µÎ¶¨¹ÜÓÃÕôÁóˮϴµÓºó¿ÉÒÔÖ±½Ó×°Òº

b£®×¶ÐÎÆ¿²»ÐèÒªÓôý²âÒ¹ÈóÏ´

c£®µÎ¶¨¹ý³ÌÖУ¬ÑÛ¾¦×¢Êӵζ¨¹ÜÖÐÒºÃæ±ä»¯

d£®µÎ¶¨½áÊøºó£¬30 sÄÚÈÜÒº²»»Ö¸´Ô­À´µÄÑÕÉ«£¬ÔÙ¶ÁÊý

£¨iii£©ÓÉ¿òͼÖÐÊý¾Ý¼ÆË㣬¿ÉµÃʯӢ¹ÜA×ó²à¹ÌÌåÖÐÌúÔªËصİٷֺ¬Á¿Îª        ¡£

 

²é¿´´ð°¸ºÍ½âÎö>>

ͬ²½Á·Ï°²á´ð°¸