\u0110\u1ec1 V\u1eadt l\u00fd th\u01b0\u1eddng d\u00e0i, nhi\u1ec1u d\u1eef li\u1ec7u, t\u1ed1n th\u1eddi gian \u0111\u1ecdc hi\u1ec3u, do \u0111\u00f3 40 c\u00e2u h\u1ecfi ho\u00e0n th\u00e0nh trong 50 ph\u00fat l\u00e0 \u00e1p l\u1ef1c l\u1edbn v\u1edbi th\u00ed sinh.<\/strong><\/em><\/p>\n

<\/p>\n

Trong k\u1ef3 thi THPT qu\u1ed1c gia 2017, V\u1eadt l\u00fd s\u1ebd l\u00e0 m\u00f4n th\u00e0nh ph\u1ea7n trong t\u1ed5 h\u1ee3p b\u00e0i thi Khoa h\u1ecdc t\u1ef1 nhi\u00ean. \u0110\u1ec1 g\u1ed3m 40 c\u00e2u tr\u1eafc nghi\u1ec7m, th\u1eddi gian 50 ph\u00fat. \u0110\u00e2y l\u00e0 \u00e1p l\u1ef1c kh\u00f4ng h\u1ec1 nh\u1ecf cho th\u00ed sinh b\u1edfi \u0111\u1ec1 V\u1eadt l\u00fd th\u01b0\u1eddng d\u00e0i, nhi\u1ec1u d\u1eef li\u1ec7u, t\u1ed1n th\u1eddi gian \u0111\u1ecdc hi\u1ec3u.<\/p>\n

Th\u1ea7y gi\u00e1o \u0110\u1ed7 Ng\u1ecdc H\u00e0 (Vi\u1ec7n V\u1eadt l\u00fd – Vi\u1ec7n H\u00e0n l\u00e2m Khoa h\u1ecdc v\u00e0 C\u00f4ng ngh\u1ec7 Vi\u1ec7t Nam) s\u1ebd b\u1eadt m\u00ed 4 m\u1eb9o x\u1eed l\u00fd c\u00e2u h\u1ecfi trong 75 gi\u00e2y c\u1ee7a m\u00f4n thi n\u00e0y.<\/p>\n

1. Ph\u00e2n b\u1ed5 th\u1eddi gian l\u00e0m b\u00e0i h\u1ee3p l\u00fd<\/strong><\/p>\n

\u0110\u1ec1 thi V\u1eadt l\u00fd c\u00f3 kho\u1ea3ng 24 c\u00e2u m\u1ee9c \u0111\u1ed9 d\u1ec5, bao g\u1ed3m l\u00fd thuy\u1ebft d\u1ec5 – trung b\u00ecnh v\u00e0 nh\u1eefng b\u00e0i t\u1eadp c\u00f3 th\u1ec3 t\u00ecm \u0111\u00e1p \u00e1n sau kho\u1ea3ng 1-2 b\u01b0\u1edbc l\u00e0m. V\u00ec v\u1eady, khi nh\u1eadn \u0111\u01b0\u1ee3c \u0111\u1ec1, h\u1ecdc sinh l\u00e0m l\u1ea7n l\u01b0\u1ee3t 24 c\u00e2u \u0111\u1ea7u ti\u00ean trong kho\u1ea3ng 10-12 ph\u00fat.<\/p>\n

16 c\u00e2u c\u00f2n l\u1ea1i c\u00f3 m\u1ee9c \u0111\u1ed9 ki\u1ebfn th\u1ee9c t\u1eeb trung b\u00ecnh \u0111\u1ebfn kh\u00f3, \u0111\u01b0\u1ee3c s\u1eafp x\u1ebfp xen k\u1ebd. H\u1ecdc sinh n\u00ean \u0111\u1ecdc l\u01b0\u1edbt to\u00e0n b\u1ed9 r\u1ed3i ch\u1ecdn ra nh\u1eefng c\u00e2u trong kh\u1ea3 n\u0103ng c\u1ee7a m\u00ecnh \u0111\u1ec3 l\u00e0m tr\u01b0\u1edbc. C\u00f2n th\u1eddi gian, th\u00ed sinh quay l\u1ea1i gi\u1ea3i quy\u1ebft c\u00e2u h\u1ecfi kh\u00f3.<\/p>\n

2. \u0110\u1ecdc ng\u01b0\u1ee3c c\u00e2u h\u1ecfi<\/strong><\/p>\n

Nhi\u1ec1u b\u00e0i t\u1eadp trong \u0111\u1ec1 thi m\u00f4n V\u1eadt l\u00fd r\u1ea5t d\u00e0i, c\u00f3 d\u1eef li\u1ec7u l\u1edbn khi\u1ebfn h\u1ecdc sinh hoang mang, m\u1ea5t kh\u00e1 nhi\u1ec1u th\u1eddi gian \u0111\u1ecdc hi\u1ec3u. V\u1edbi nh\u1eefng c\u00e2u n\u00e0y, th\u00ed sinh n\u00ean \u00e1p d\u1ee5ng k\u1ef9 n\u0103ng \u0111\u1ecdc ng\u01b0\u1ee3c \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh nhanh y\u00eau c\u1ea7u c\u1ee7a \u0111\u1ec1 l\u00e0 g\u00ec. C\u00e2u h\u1ecfi n\u00e0y th\u01b0\u1eddng \u0111\u01b0\u1ee3c \u0111\u01b0a ra \u1edf \u00fd cu\u1ed1i c\u00f9ng c\u1ee7a \u0111\u1ec1.<\/p>\n

B\u00e1m s\u00e1t y\u00eau c\u1ea7u \u0111\u00f3, th\u00ed sinh s\u00e0ng l\u1ecdc d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c \u0111\u01b0a ra \u1edf ph\u00eda tr\u00ean r\u1ed3i x\u00e2y d\u1ef1ng h\u01b0\u1edbng l\u00e0m b\u00e0i. Ph\u01b0\u01a1ng ph\u00e1p n\u00e0y s\u1ebd gi\u00fap h\u1ecdc sinh hi\u1ec3u \u0111\u00fang, tr\u00fang, nhanh y\u00eau c\u1ea7u c\u1ee7a \u0111\u1ec1 v\u00e0 ti\u1ebft ki\u1ec7m th\u1eddi gian gi\u1ea3i h\u01a1n.<\/p>\n

3. \u0110\u00e1nh gi\u00e1 m\u1ee9c \u0111\u1ed9 tin t\u01b0\u1edfng c\u1ee7a \u0111\u00e1p \u00e1n<\/strong><\/p>\n

Th\u1eddi gian trung b\u00ecnh \u0111\u1ec3 ho\u00e0n th\u00e0nh m\u1ed9t c\u00e2u h\u1ecfi tr\u1eafc nghi\u1ec7m V\u1eadt l\u00fd l\u00e0 75 gi\u00e2y. V\u1edbi m\u1ed9t s\u1ed1 b\u00e0i t\u1eadp, h\u1ecdc sinh c\u1ea7n c\u00f3 k\u1ef9 n\u0103ng l\u00e0m b\u00e0i nhanh \u0111\u1ec3 r\u00fat ng\u1eafn th\u1eddi gian, trong \u0111\u00f3 c\u00f3 k\u1ef9 n\u0103ng \u0111\u00e1nh gi\u00e1 m\u1ee9c \u0111\u1ed9 tin t\u01b0\u1edfng c\u1ee7a c\u00e1c \u0111\u00e1p \u00e1n. \u0110\u1ec3 l\u00e0m \u0111\u01b0\u1ee3c \u0111i\u1ec1u n\u00e0y, th\u00ed sinh c\u1ea7n n\u1eafm ch\u1eafc b\u1ea3n ch\u1ea5t l\u00fd thuy\u1ebft \u0111\u1ec3 bi\u1ebft \u0111\u01b0\u1ee3c kho\u1ea3ng gi\u00e1 tr\u1ecb \u1edf c\u00e1c \u0111\u1ea1i l\u01b0\u1ee3ng \u0111\u01b0\u1ee3c h\u1ecfi, t\u1eeb \u0111\u00f3 \u0111\u00e1nh gi\u00e1 m\u1ee9c \u0111\u1ed9 \u0111\u00fang\/sai\/tin t\u01b0\u1edfng c\u1ee7a \u0111\u00e1p \u00e1n.<\/p>\n

V\u00ed d\u1ee5, \u0111\u1ec1 thi \u0111\u1ea1i h\u1ecdc n\u0103m 2012 h\u1ecfi: Bi\u1ebft c\u00f4ng tho\u00e1t electron c\u1ee7a c\u00e1c kim lo\u1ea1i canxi, kali, b\u1ea1c v\u00e0 \u0111\u1ed3ng l\u1ea7n l\u01b0\u1ee3t l\u00e0: 2,89eV; 2,26eV; 4,78eV va 4,14eV. Chi\u1ebfu \u00e1nh s\u00e1ng c\u00f3 b\u01b0\u1edbc s\u00f3ng 0,33\u00b5m v\u00e0o b\u1ec1 m\u1eb7t c\u00e1c kim lo\u1ea1i tr\u00ean.<\/p>\n

Hi\u1ec7n t\u01b0\u1ee3ng quang \u0111i\u1ec7n kh\u00f4ng x\u1ea3y ra v\u1edbi c\u00e1c kim lo\u1ea1i n\u00e0o sau \u0111\u00e2y:<\/p>\n

A. Canxi v\u00e0 b\u1ea1c;
\nB. Kali v\u00e0 \u0111\u1ed3ng;
\nC. Kali v\u00e0 canxi;
\nD. B\u1ea1c v\u00e0 \u0111\u1ed3ng<\/p>\n

V\u1edbi \u0111\u1ec1 n\u00e0y, theo c\u00e1ch b\u00ecnh th\u01b0\u1eddng, h\u1ecdc sinh s\u1ebd \u0111i t\u00ednh n\u0103ng l\u01b0\u1ee3ng ph\u00f4ton c\u1ee7a b\u1ee9c x\u1ea1 chi\u1ebfu v\u00e0o sau \u0111\u00f3 so s\u00e1nh v\u1edbi c\u00e1c c\u00f4ng tho\u00e1t c\u1ee7a c\u00e1c kim lo\u1ea1i \u0111\u1ec3 t\u00ecm ra \u0111\u00e1p \u00e1n. \u0110i\u1ec1u n\u00e0y s\u1ebd m\u1ea5t kho\u1ea3ng 1 ph\u00fat 30 gi\u00e2y.<\/p>\n

Tuy nhi\u00ean, th\u00ed sinh c\u00f3 th\u1ec3 ch\u1ecdn \u0111\u01b0\u1ee3c r\u1ea5t nhanh \u0111\u00e1p \u00e1n ch\u00ednh x\u00e1c, khi s\u1eed d\u1ee5ng ph\u01b0\u01a1ng ph\u00e1p lo\u1ea1i tr\u1eeb, n\u1ebfu n\u1eafm ch\u1eafc l\u00fd thuy\u1ebft. \u1ede \u0111\u00e2y, c\u00e1c kim lo\u1ea1i b\u1ea1c, \u0111\u1ed3ng, k\u1ebdm, nh\u00f4m\u2026 c\u00f3 gi\u1edbi h\u1ea1n quang \u0111i\u1ec7n n\u1eb1m \u1edf khu v\u1ef1c t\u1eed ngo\u1ea1i, c\u00f2n c\u00e1c kim lo\u1ea1i ki\u1ec1m – ki\u1ec1m th\u1ed5 (canxi, kali..) c\u00f3 gi\u1edbi h\u1ea1n quang \u0111i\u1ec7n n\u1eb1m \u1edf khu v\u1ef1c \u00e1nh s\u00e1ng nh\u00ecn th\u1ea5y. Khi ch\u00fang ta chi\u1ebfu m\u1ed9t \u00e1nh s\u00e1ng c\u00f3 b\u01b0\u1edbc s\u00f3ng 0,33\u00b5m – l\u00e0 b\u01b0\u1edbc s\u00f3ng khu v\u1ef1c t\u1eed ngo\u1ea1i s\u1ebd g\u00e2y ra hi\u1ec7n t\u01b0\u1ee3ng quang \u0111i\u1ec7n ngo\u00e0i \u0111\u1ed1i v\u1edbi c\u00e1c kim lo\u1ea1i ki\u1ec1m, ki\u1ec1m th\u1ed5 (\u0111\u00f3 l\u00e0 canxi, kali). Do \u0111\u00f3, ch\u00fang ta lo\u1ea1i \u0111\u01b0\u1ee3c \u0111\u00e1p \u00e1n A, B, C do c\u00f3 ch\u1ee9a canxi v\u00e0 kali. \u0110\u00e1p \u00e1n ch\u00ednh x\u00e1c c\u00f2n l\u1ea1i l\u00e0 D, nhanh ch\u00f3ng \u0111\u01b0\u1ee3c t\u00ecm ra.<\/p>\n

V\u00ed d\u1ee5 tr\u00ean c\u00e0ng kh\u1eb3ng \u0111\u1ecbnh \u0111\u01b0\u1ee3c vai tr\u00f2 quan tr\u1ecdng c\u1ee7a vi\u1ec7c h\u1ecdc, hi\u1ec3u l\u00fd thuy\u1ebft trong s\u00e1ch gi\u00e1o khoa. Vi\u1ec7c n\u1eafm v\u1eefng l\u00fd thuy\u1ebft kh\u00f4ng ch\u1ec9 gi\u00fap h\u1ecdc sinh l\u00e0m t\u1ed1t c\u00e2u h\u1ecfi l\u00fd thuy\u1ebft m\u00e0 c\u00f2n gi\u1ea3i quy\u1ebft r\u1ea5t nhanh ch\u00f3ng b\u00e0i t\u1eadp.<\/p>\n

4. Nh\u00e1p khoa h\u1ecdc<\/strong><\/p>\n

\u0110\u1ed1i v\u1edbi nh\u1eefng c\u00e2u h\u1ecfi b\u00e0i t\u1eadp trung b\u00ecnh, ch\u1ec9 c\u00f3 2-3 ph\u00e9p t\u00ednh, ch\u00fang ta n\u00ean nh\u00e1p tr\u1ef1c ti\u1ebfp v\u00e0o \u0111\u1ec1. Nh\u01b0ng nh\u1eefng b\u00e0i t\u1eadp ph\u1ee9c t\u1ea1p h\u01a1n, h\u1ecdc sinh n\u00ean nh\u00e1p ra ngo\u00e0i m\u1ed9t c\u00e1ch r\u00f5 r\u00e0ng, ng\u1eafn g\u1ecdn, m\u1ea1ch l\u1ea1c. Qu\u00e1 tr\u00ecnh n\u00e0y, h\u1ecdc sinh s\u1ebd ghi l\u1ea1i \u0111\u01b0\u1ee3c nh\u1eefng \u0111\u1ea1i l\u01b0\u1ee3ng \u0111\u00e3 t\u00ecm ra \u0111\u1ec3 n\u1ebfu v\u00ec b\u00e0i qu\u00e1 kh\u00f3, th\u00ed sinh t\u1ea1m b\u1ecf qua v\u00e0 l\u00e0m b\u00e0i t\u1eadp kh\u00e1c, th\u00ec khi quay l\u1ea1i gi\u1ea3i quy\u1ebft, c\u00e1c em s\u1ebd kh\u00f4ng c\u1ea7n t\u00ednh l\u1ea1i nh\u1eefng \u0111\u1ea1i l\u01b0\u1ee3ng n\u00e0y. \u0110\u00e2y l\u00e0 \u0111i\u1ec1u \u00edt h\u1ecdc sinh ch\u00fa \u00fd.<\/p>\n

\u0110\u1ed7 Ng\u1ecdc H\u00e0<\/strong>
\nH\u1ec7 th\u1ed1ng Gi\u00e1o d\u1ee5c Hocmai<\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

\u0110\u1ec1 V\u1eadt l\u00fd th\u01b0\u1eddng d\u00e0i, nhi\u1ec1u d\u1eef li\u1ec7u, t\u1ed1n th\u1eddi gian \u0111\u1ecdc hi\u1ec3u, do \u0111\u00f3 40 c\u00e2u h\u1ecfi ho\u00e0n th\u00e0nh trong 50 ph\u00fat l\u00e0 \u00e1p l\u1ef1c l\u1edbn v\u1edbi th\u00ed sinh. Trong k\u1ef3 thi THPT qu\u1ed1c gia 2017, V\u1eadt l\u00fd s\u1ebd l\u00e0 m\u00f4n th\u00e0nh ph\u1ea7n trong t\u1ed5 h\u1ee3p b\u00e0i thi Khoa h\u1ecdc t\u1ef1 nhi\u00ean. \u0110\u1ec1 g\u1ed3m […]<\/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":[158],"tags":[],"yoast_head":"\n