Ngo\u00e0i n\u1eafm v\u1eefng ki\u1ebfn th\u1ee9c s\u00e1ch gi\u00e1o khoa v\u00e0 suy lu\u1eadn \u0111\u1ec3 gi\u1ea3i quy\u1ebft b\u00e0i kh\u00f3, h\u1ecdc sinh c\u1ea7n bi\u1ebft c\u00e1c b\u1eaby th\u01b0\u1eddng g\u1eb7p trong \u0111\u1ec1 thi.<\/h5>\n

\n

\n

Th\u1ea1c s\u0129 Nguy\u1ec5n Anh Tu\u1ea5n, gi\u00e1o vi\u00ean tr\u01b0\u1eddng THPT chuy\u00ean H\u00e0 N\u1ed9i – Amsterdam, c\u00f3 18 n\u0103m kinh nghi\u1ec7m luy\u1ec7n thi m\u00f4n H\u00f3a. Theo th\u1ea7y, v\u1ed9i v\u00e0ng trong kh\u00e2u \u0111\u1ecdc \u0111\u1ec1 l\u00e0 y\u1ebfu t\u1ed1 \u0111\u1ea7u ti\u00ean khi\u1ebfn h\u1ecdc sinh m\u1ea5t \u0111i\u1ec3m.<\/p>\n

C\u1ea7n b\u00ecnh t\u0129nh \u0111\u1ecdc k\u1ef9 \u0111\u1ec1 b\u00e0i \u0111\u1ec3 tr\u00e1nh b\u1eaby<\/strong><\/p>\n

N\u1ebfu kh\u00f4ng t\u1eadp trung v\u00e0 kh\u00f4ng b\u00ecnh t\u0129nh th\u00ec h\u1ecdc sinh s\u1ebd r\u1ea5t d\u1ec5 m\u1eafc sai l\u1ea7m trong c\u00e1c ki\u1ec3u c\u00e2u h\u1ecfi c\u00f3 b\u1eaby, nh\u01b0 m\u1ed9t s\u1ed1 v\u00ed d\u1ee5 sau:<\/p>\n

– B\u1eaby v\u1ec1 ki\u1ebfn th\u1ee9c l\u00fd thuy\u1ebft:<\/p>\n

Vi\u1ec7c h\u1ecdc l\u00fd thuy\u1ebft kh\u00f4ng k\u1ef9 c\u00f3 th\u1ec3 g\u00e2y nh\u1ea7m l\u1eabn trong nh\u1eefng c\u00e2u h\u1ecfi thu\u1ed9c ph\u1ea7n ki\u1ebfn th\u1ee9c tr\u1ecdng t\u00e2m.<\/p>\n

Ch\u1eb3ng h\u1ea1n, b\u1eaby ph\u1ea3n \u1ee9ng c\u1ee7a s\u1eaft \u0111\u01a1n ch\u1ea5t (Fe) v\u1edbi ch\u1ea5t oxy h\u00f3a m\u1ea1nh nh\u01b0 HNO_{3<\/sub>, H2<\/sub>SO4<\/sub>\u00a0\u0111\u1eb7c n\u00f3ng. Nhi\u1ec1u h\u1ecdc sinh v\u1ed9i v\u00e0ng th\u01b0\u1eddng k\u1ebft lu\u1eadn trong tr\u01b0\u1eddng h\u1ee3p n\u00e0y Fe s\u1ebd t\u1ea1o ion Fe^{3+<\/sup>, nh\u01b0ng th\u1ef1c t\u1ebf n\u1ebfu Fe d\u01b0, ph\u1ea3n \u1ee9ng ho\u00e0n to\u00e0n th\u00ec s\u1ea3n ph\u1ea9m cu\u1ed1i c\u00f9ng l\u00e0 Fe2+<\/sup>. Ho\u1eb7c n\u1ebfu c\u00e1c ch\u1ea5t \u0111\u1ec1u h\u1ebft, c\u00f3 th\u1ec3 t\u1ea1o c\u1ea3 hai d\u1ea1ng ion s\u1eaft.<\/p>\n}}

– B\u1eaby v\u1ec1 ng\u00f4n ng\u1eef c\u1ee7a \u0111\u1ec1:<\/p>\n

\u00a0Nhi\u1ec1u khi h\u1ecdc sinh kh\u00f4ng suy ngh\u0129 k\u1ef9 v\u1ec1 nh\u1eefng t\u1eeb xu\u1ea5t hi\u1ec7n trong \u0111\u1ec1 b\u00e0i, d\u1eabn \u0111\u1ebfn hi\u1ec3u l\u1ea7m \u0111\u1ec1.<\/p>\n

V\u00ed d\u1ee5:\u00a0X\u00e0 ph\u00f2ng h\u00f3a h\u1ebft<\/u><\/em><\/strong>\u00a0a gam etylaxetat\u00a0b\u1eb1ng<\/u><\/strong>\u00a0120ml dung d\u1ecbch NaOH 2M, sau ph\u1ea3n \u1ee9ng c\u00f4 c\u1ea1n dung d\u1ecbch \u0111\u01b0\u1ee3c 18 gam\u00a0ch\u1ea5t r\u1eafn.<\/u><\/strong>\u00a0T\u00ecm gi\u00e1 tr\u1ecb c\u1ee7a a?<\/em><\/p>\n

Kh\u00f4ng \u00edt h\u1ecdc sinh hi\u1ec3u l\u1ea7m \u0111\u1ec1 l\u00e0 l\u01b0\u1ee3ng NaOH ph\u1ea3n \u1ee9ng v\u1eeba \u0111\u1ee7 r\u1ed3i t\u00ednh theo s\u1ed1 mol c\u1ee7a NaOH ban \u0111\u1ea7u, ho\u1eb7c t\u01b0\u1edfng r\u1eb1ng 18 gam ch\u1ea5t r\u1eafn l\u00e0 mu\u1ed1i natri axetat r\u1ed3i t\u00ednh theo s\u1ed1 mol c\u1ee7a mu\u1ed1i. Th\u1ef1c ch\u1ea5t \u1edf \u0111\u00e2y ch\u1ec9 este h\u1ebft c\u00f2n NaOH c\u00f3 th\u1ec3 c\u00f2n d\u01b0 v\u00e0 ch\u1ea5t r\u1eafn c\u00f3 th\u1ec3 ch\u1ee9a NaOH.<\/p>\n

B\u1edfi v\u1eady h\u1ecdc sinh c\u1ea7n \u0111\u1eb7t \u1ea9n s\u1ed1 cho s\u1ed1 mol c\u1ee7a este, l\u1eadp ph\u01b0\u01a1ng tr\u00ecnh ph\u1ea3n \u1ee9ng x\u00e0 ph\u00f2ng h\u00f3a v\u00e0 gi\u1ea3i theo s\u1ed1 mol c\u1ee7a este.<\/p>\n\n\n\n\n

<\/td>\n<\/tr>\n

\n Th\u1ea7y Nguy\u1ec5n Anh Tu\u1ea5n \u0111\u00e3 c\u00f3 18 n\u0103m kinh nghi\u1ec7m luy\u1ec7n thi m\u00f4n H\u00f3a h\u1ecdc. \u1ea2nh: NVCC<\/em><\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Kh\u00f4ng n\u00ean l\u00e0m nh\u1eefng c\u00e2u t\u00ednh to\u00e1n tr\u01b0\u1edbc<\/strong><\/p>\n V\u1edbi \u0111\u1ec1 thi n\u0103m nay s\u1ed1 l\u01b0\u1ee3ng c\u00e2u l\u00fd thuy\u1ebft v\u00e0 c\u00e2u t\u00ednh to\u00e1n theo t\u1ef7 l\u1ec7 kho\u1ea3ng 60\/40. Do v\u1eady, h\u1ecdc sinh c\u1ea7n bi\u1ebft c\u00e1ch ph\u00e2n b\u1ed1 th\u1eddi gian h\u1ee3p l\u00fd khi l\u00e0m b\u00e0i.<\/p>\n H\u1ecdc sinh th\u01b0\u1eddng t\u1eadp trung cho c\u00e1c c\u00e2u h\u1ecfi t\u00ednh to\u00e1n n\u00ean b\u1ecb t\u1ed1n qu\u00e1 nhi\u1ec1u th\u1eddi gian cho c\u00e1c c\u00e2u kh\u00f3 v\u00e0 c\u00e2u h\u1ecfi c\u00f3 b\u1eaby, \u0111\u1ebfn khi s\u1eafp h\u1ebft gi\u1edd th\u00ec m\u1edbi tr\u1ea3 l\u1eddi c\u00e2u h\u1ecfi l\u00fd thuy\u1ebft.<\/p>\n Trong khi \u0111\u00f3, m\u1ed7i c\u00e2u h\u1ecfi \u0111\u1ec1u mang l\u1ea1i 0,25 \u0111i\u1ec3m, c\u00e1c c\u00e2u h\u1ecfi l\u00fd thuy\u1ebft th\u01b0\u1eddng kh\u00f4ng kh\u00f3 v\u00e0 ch\u1ec9 c\u1ea7n b\u00ecnh t\u0129nh \u0111\u1ecdc k\u1ef9 l\u00e0 tr\u1ea3 l\u1eddi \u0111\u00fang. V\u00ec th\u1ebf, h\u1ecdc sinh n\u00ean \u01b0u ti\u00ean c\u00e1c c\u00e2u h\u1ecfi l\u00fd thuy\u1ebft v\u00e0 c\u00e2u h\u1ecfi d\u1ec5 tr\u01b0\u1edbc.<\/p>\n C\u00e2u h\u1ecfi s\u01a1 \u0111\u1ed3 chuy\u1ec3n h\u00f3a ho\u1eb7c c\u00e2u bi\u1ec3u b\u1ea3ng trong \u0111\u1ec1 th\u01b0\u1eddng d\u00e0i, nhi\u1ec1u d\u1eef ki\u1ec7n. \u0110\u1ec3 ti\u1ebft ki\u1ec7m th\u1eddi gian, h\u1ecdc sinh n\u00ean d\u1ef1a v\u00e0o ch\u1ea5t \u0111\u00e3 suy lu\u1eadn ra \u0111\u01b0\u1ee3c \u0111\u1ec3 lo\u1ea1i d\u1ea7n \u0111\u00e1p \u00e1p. M\u1eabu c\u00e2u n\u00e0y, th\u01b0\u1eddng kh\u00f4ng c\u1ea7n lu\u1eadn h\u1ebft c\u00e1c d\u1eef ki\u1ec7n v\u1eabn t\u00ecm \u0111\u01b0\u1ee3c \u0111\u00e1p \u00e1n \u0111\u00fang.<\/p>\n V\u1edbi c\u00e1c b\u00e0i t\u1eadp t\u00ednh to\u00e1n kh\u00f3 (tr\u00ean m\u1ee9c 8 \u0111i\u1ec3m), h\u1ecdc sinh n\u00ean t\u00f3m t\u1eaft b\u00e0i theo s\u01a1 \u0111\u1ed3, suy lu\u1eadn k\u1ef9 r\u1ed3i gi\u1ea3i. M\u1eabu c\u00e2u h\u1ecfi n\u00e0y th\u01b0\u1eddng \u00e1p d\u1ee5ng k\u1ebft h\u1ee3p nhi\u1ec1u ph\u01b0\u01a1ng ph\u00e1p b\u1ea3o to\u00e0n.<\/p>\n Tr\u00e1nh vi\u1ec7c h\u1ecdc th\u1ee7 thu\u1eadt v\u00e0 nh\u1eefng b\u00e0i kh\u00f3<\/strong><\/p>\n Nhi\u1ec1u h\u1ecdc sinh khi luy\u1ec7n thi THPT qu\u1ed1c gia v\u1eabn \u1ea3o t\u01b0\u1edfng v\u1ec1 m\u1ee9c \u0111\u1ed9 kh\u00f3 c\u1ee7a \u0111\u1ec1 n\u00ean h\u1ecdc to\u00e0n nh\u1eefng ki\u1ebfn th\u1ee9c cao si\u00eau, hay th\u1ee7 thu\u1eadt gi\u1ea3i \u0111\u1ec1 tr\u1eafc nghi\u1ec7m m\u00e0 kh\u00f4ng c\u1ea7n hi\u1ec3u b\u1ea3n ch\u1ea5t.<\/p>\n Nh\u01b0ng th\u1ef1c t\u1ebf, ba \u0111\u1ec1 thi m\u00e0 B\u1ed9 Gi\u00e1o d\u1ee5c v\u00e0 \u0110\u00e0o t\u1ea1o gi\u1edbi thi\u1ec7u r\u1ea5t chu\u1ea9n ki\u1ebfn th\u1ee9c theo ch\u01b0\u01a1ng tr\u00ecnh s\u00e1ch gi\u00e1o khoa c\u01a1 b\u1ea3n l\u1edbp 12. C\u00f3 kho\u1ea3ng 12 c\u00e2u l\u00e0 m\u1ee9c \u0111\u1ed9 bi\u1ebft, 12 c\u00e2u m\u1ee9c \u0111\u1ed9 hi\u1ec3u (24 c\u00e2u n\u00e0y t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u1edbi b\u00e0i t\u1eadp trong s\u00e1ch gi\u00e1o khoa) v\u00e0 kho\u1ea3ng 16 c\u00e2u y\u00eau c\u1ea7u h\u1ecdc sinh ph\u1ea3i hi\u1ec3u b\u1ea3n ch\u1ea5t v\u00e0 v\u1eadn d\u1ee5ng m\u1edf r\u1ed9ng, n\u00e2ng cao.<\/p>\n V\u00ec v\u1eady trong giai \u0111o\u1ea1n n\u01b0\u1edbc r\u00fat n\u00e0y, h\u1ecdc sinh c\u1ea7n r\u00e0 so\u00e1t ki\u1ebfn th\u1ee9c s\u00e1ch gi\u00e1o khoa theo khung ch\u01b0\u01a1ng tr\u00ecnh thi m\u00e0 B\u1ed9 Gi\u00e1o d\u1ee5c v\u00e0 \u0110\u00e0o t\u1ea1o h\u01b0\u1edbng d\u1eabn \u0111\u1ec3 \u00f4n luy\u1ec7n nh\u1eefng v\u00f9ng ki\u1ebfn th\u1ee9c m\u00e0 m\u00ecnh ch\u01b0a n\u1eafm ch\u1eafc, tr\u00e1nh vi\u1ec7c h\u1ecdc thu\u1ed9c l\u00f2ng m\u00e1y m\u00f3c hay ch\u1ec9 t\u1eadp trung v\u00e0o vi\u1ec7c h\u1ecdc th\u1ee7 thu\u1eadt, m\u1eb9o gi\u1ea3i \u0111\u1ec1.<\/p>\n V\u1edbi kinh nghi\u1ec7m 18 n\u0103m luy\u1ec7n thi, t\u00f4i kh\u1eb3ng \u0111\u1ecbnh \u0111\u1ec1 thi m\u00f4n H\u00f3a h\u00e0ng n\u0103m \u0111\u1ec1u kh\u00f4ng c\u00f3 m\u1eb9o \u0111\u1ec3 ch\u1ecdn \u0111\u00e1p \u00e1n. T\u1ea5t c\u1ea3 c\u00e2u h\u1ecfi t\u1eeb d\u1ec5 \u0111\u1ebfn kh\u00f3 \u0111\u1ec1u xu\u1ea5t ph\u00e1t t\u1eeb b\u1ea3n ch\u1ea5t h\u00f3a h\u1ecdc, suy lu\u1eadn r\u1ed3i gi\u1ea3i theo c\u00e1c ph\u01b0\u01a1ng ph\u00e1p \u0111\u1eb7c th\u00f9 c\u1ee7a b\u1ed9 m\u00f4n.<\/p>\n T\u00f4i nh\u1ea5n m\u1ea1nh m\u1ed9t l\u1ea7n n\u1eefa ph\u01b0\u01a1ng ch\u00e2m t\u1ed1t nh\u1ea5t trong th\u1eddi gian cu\u1ed1i n\u00e0y l\u00e0 h\u1ecdc th\u1eadt k\u1ef9 s\u00e1ch gi\u00e1o khoa c\u01a1 b\u1ea3n, kh\u00f4ng lao v\u00e0o nh\u1eefng b\u00e0i t\u1eadp kh\u00f3, tr\u00e1nh h\u1ecdc d\u1ed3n d\u1eadp g\u00e2y c\u0103ng th\u1eb3ng.<\/p>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":" Ngo\u00e0i n\u1eafm v\u1eefng ki\u1ebfn th\u1ee9c s\u00e1ch gi\u00e1o khoa v\u00e0 suy lu\u1eadn \u0111\u1ec3 gi\u1ea3i quy\u1ebft b\u00e0i kh\u00f3, h\u1ecdc sinh c\u1ea7n bi\u1ebft c\u00e1c b\u1eaby th\u01b0\u1eddng g\u1eb7p trong \u0111\u1ec1 thi. Th\u1ea1c s\u0129 Nguy\u1ec5n Anh Tu\u1ea5n, gi\u00e1o vi\u00ean tr\u01b0\u1eddng THPT chuy\u00ean H\u00e0 N\u1ed9i – Amsterdam, c\u00f3 18 n\u0103m kinh nghi\u1ec7m luy\u1ec7n thi m\u00f4n H\u00f3a. Theo th\u1ea7y, v\u1ed9i v\u00e0ng trong […]<\/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":[159],"tags":[],"yoast_head":"\n