B\u00e0i 1 (trang 155 SGK H\u00f3a 12):\u00a0Vi\u1ebft ph\u01b0\u01a1ng tr\u00ecnh h\u00f3a h\u1ecdc c\u1ee7a c\u00e1c ph\u1ea3n \u1ee9ng trong d\u00e3y chuy\u1ec3n h\u00f3a sau:<\/strong><\/p>\n Cr \u2192 Cr2<\/sub>O3<\/sub>\u00a0\u2192 Cr2<\/sub>(SO4<\/sub>)3<\/sub>\u00a0\u2192 Cr(OH)3<\/sub>\u00a0\u2192 Cr2<\/sub>O3<\/sub><\/strong><\/p>\n L\u1eddi gi\u1ea3i:<\/b><\/p>\n (1) 4Cr + 3O2<\/sub>\u00a0\u2192 2Cr2<\/sub>O3<\/sub><\/p>\n (2) Cr2<\/sub>O3<\/sub>\u00a0+ H2<\/sub>SO4<\/sub>\u00a0\u2192 Cr2<\/sub>(SO4<\/sub>)3<\/sub>\u00a0+ H2<\/sub>O<\/p>\n (3) Cr2<\/sub>(SO4<\/sub>)3<\/sub>\u00a0+ 6NaOH \u2192 2Cr(OH)3<\/sub>\u00a0+ 3Na2<\/sub>SO4<\/sub><\/p>\n (4) 2Cr(OH)3<\/sub>\u00a0\u2192 Cr2<\/sub>O3<\/sub>\u00a0+ 3H2<\/sub>O<\/p>\n B\u00e0i 2 (trang 155 SGK H\u00f3a 12):\u00a0C\u1ea5u h\u00ecnh electron c\u1ee7a ion Cr3+<\/sup>\u00a0l\u00e0 ph\u01b0\u01a1ng \u00e1n n\u00e0o?<\/strong><\/p>\n A.[Ar] 3d5<\/sup><\/p>\n B.[Ar] 3d4<\/sup><\/p>\n C.[Ar] 3d3<\/sup><\/p>\n D.[Ar] 3d2<\/sup><\/p>\n L\u1eddi gi\u1ea3i:<\/b><\/p>\n \u0110\u00e1p \u00e1n C.<\/p>\n B\u00e0i 3 (trang 155 SGK H\u00f3a 12):\u00a0C\u00e1c s\u1ed1 oxi h\u00f3a \u0111\u1eb7c tr\u01b0ng c\u1ee7a crom l\u00e0 ph\u01b0\u01a1ng \u00e1n n\u00e0o?<\/strong><\/p>\n A. +2, +4, +6.<\/p>\n B. +2, +3, +6.<\/p>\n C. +1, +2, +4, +6.<\/p>\n D. +3, +4, +6.<\/p>\n L\u1eddi gi\u1ea3i:<\/b><\/p>\n \u0110\u00e1p \u00e1n B.<\/p>\n B\u00e0i 4 (trang 155 SGK H\u00f3a 12):\u00a0H\u00e3y vi\u1ebft c\u00f4ng th\u1ee9c c\u1ee7a m\u1ed9t s\u1ed1 mu\u1ed1i trong \u0111\u00f3 nguy\u00ean t\u1ed1 crom<\/strong><\/p>\n a) \u0110\u00f3ng vai tr\u00f2 cation.<\/p>\n b) C\u00f3 trong th\u00e0nh ph\u1ea7n c\u1ee7a anion.<\/p>\n L\u1eddi gi\u1ea3i:<\/b><\/p>\n Mu\u1ed1i m\u00e0 crom \u0111\u00f3ng vai tr\u00f2 c\u1ee7a cation : Cr2<\/sub>(SO4<\/sub>)3<\/sub>, CrCl3<\/sub>, CrSO4<\/sub><\/p>\n Mu\u1ed1i m\u00e0 crom c\u00f3 trong th\u00e0nh ph\u1ea7n c\u1ee7a anion : K2<\/sub>Cr2<\/sub>O7<\/sub>, Na2<\/sub>CrO4<\/sub><\/p>\n B\u00e0i 5 (trang 155 SGK H\u00f3a 12):\u00a0Khi nung n\u00f3ng 2 mol natri \u0111icromat ng\u01b0\u1eddi ta thu \u0111\u01b0\u1ee3c 48 gam O2<\/sub>\u00a0v\u00e0 1 mol crom (III) oxit. H\u00e3y vi\u1ebft ph\u01b0\u01a1ng tr\u00ecnh h\u00f3a h\u1ecdc c\u1ee7a ph\u1ea3n \u1ee9ng v\u00e0 xem x\u00e9t natri \u0111icromat \u0111\u00e3 b\u1ecb nhi\u1ec7t ph\u00e2n ho\u00e0n to\u00e0n ch\u01b0a?<\/strong><\/p>\n L\u1eddi gi\u1ea3i:<\/b><\/p>\n 2Na2<\/sub>Cr2<\/sub>O7<\/sub>\u00a0\u2192 2Na2<\/sub>O + 2Cr2<\/sub>O3<\/sub>\u00a0+ 3O2<\/sub><\/p>\n S\u1ed1 mol O2<\/sub>\u00a0l\u00e0 nO2<\/sub>\u00a0= 48 \/ 32 = 1,5(mol)<\/p>\n S\u1ed1 mol Na2<\/sub>Cr2<\/sub>O7<\/sub>\u00a0nNa2Cr2O7<\/sub>= 2\/3 x nO2<\/sub>\u00a0= 1(mol)<\/p>\n Nung 2 mol Na2<\/sub>Cr2<\/sub>O7<\/sub>\u00a0n\u1ebfu thu 48 gam O2<\/sub>\u00a0th\u00ec ch\u1ec9 nung h\u1ebft 1 (mol). Do \u0111\u00f3 ph\u1ea3n \u1ee9ng ch\u01b0a k\u1ebft th\u00fac.<\/p>\n","protected":false},"excerpt":{"rendered":" B\u00e0i 1 (trang 155 SGK H\u00f3a 12):\u00a0Vi\u1ebft ph\u01b0\u01a1ng tr\u00ecnh h\u00f3a h\u1ecdc c\u1ee7a c\u00e1c ph\u1ea3n \u1ee9ng trong d\u00e3y chuy\u1ec3n h\u00f3a sau: Cr \u2192 Cr2O3\u00a0\u2192 Cr2(SO4)3\u00a0\u2192 Cr(OH)3\u00a0\u2192 Cr2O3 L\u1eddi gi\u1ea3i: (1) 4Cr + 3O2\u00a0\u2192 2Cr2O3 (2) Cr2O3\u00a0+ H2SO4\u00a0\u2192 Cr2(SO4)3\u00a0+ H2O (3) Cr2(SO4)3\u00a0+ 6NaOH \u2192 2Cr(OH)3\u00a0+ 3Na2SO4 (4) 2Cr(OH)3\u00a0\u2192 Cr2O3\u00a0+ 3H2O B\u00e0i 2 (trang 155 SGK H\u00f3a 12):\u00a0C\u1ea5u […]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_mi_skip_tracking":false,"tdm_status":"","tdm_grid_status":""},"categories":[1305],"tags":[1419,1420],"yoast_head":"\n