Ua kev tshua - dawb thiab yooj yim!

Muaj ntau cov tub ntxhais kawm tsis txaus siab hais tias lawv tsis to taub txog cov Science News for KIDS thiab xav txog nws ib tug ntawm cov feem ntau nyuaj lub tsev kawm ntawv kev kawm. Piv txwv li, ib tug kab lus "ua kev tshuaj tiv thaiv" xav ntau menyuam kawm ntawv ntshai. Nyob rau hauv ib co txoj kev, lawv yeej tsis ntseeg txoj cai. Tsis tau nrog Science News for KIDS muaj peev xwm thiab yuav tsum phooj ywg. Nws nyob puag ncig peb lub neej qhov txhia chaw. Feem ntau cov zoo tswv yim rau cov menyuam kawm ntawv uas yog txiav txim los mus ua kom cov phooj ywg nrog no yooj yim science - ib tug xib fwb los qhia ib tug muab cov ntaub ntawv uas rau txhua zaj lus qhia. Los npaj rau cov chav kawm nyob rau ntawm lub hauv paus ntsiab lus: "Hnub no kuv tsis tau thov - ces koj yuav tsis qhia!", Tab sis nyob rau hauv lub hauv paus ntsiab lus: "Kuv xav paub thiab to taub txhua yam, txawm yog li ntawd yuav kawm tau dab tsi kuv tsis tau thov!". Tsuas yog nrog xws li ib mus kom ze rau ua lag ua luam Science News for KIDS yuav ua tau rau koj ib tug qhib phau ntawv. Thiab koj yuav to taub thiab paub tias nws nyob rau hauv tag nrho cov yam ntawm peb lub neej.

Nyob rau hauv no tsab xov xwm peb yuav tsom tsuas yog nyob rau qhov no tshuaj tshaj plaws raws li ib tug ua kev tshuaj tiv thaiv. Yuav ua li cas to taub qhov no lub sij hawm? Yog hais tias lo lus tshuaj tiv thaiv yog ntau dua los yog tsawg ntshiab (nws yog hais txog mus rau lub sib tham ntawm tshuaj), nyob ntawm no nrog cov lus "ua kev" - nyob rau hauv ntau lub tsev kawm ntawv cov teeb meem. Ntawm no yog peb yuav tsum nco qab tus neeg txhais lus ntawm cov Greek lo lus "geteros" - thiaj li sib txawv, ntau haiv neeg.

Ua kev tshuaj tiv thaiv: piv txwv ntawm lub neej

Ua kev tshua muab qhov chaw ntawm qhov sib txawv nyob rau hauv cov xwm, tab sis, theej lub cev lub xeev ntawm cov tshuaj yeeb dej caw. Lwm ntawm cov thawj lub tsev kawm ntawv cov menyuam kawm ntawv paub hais tias tej yam khoom uas tej zaum yuav nyob rau hauv lub xeev ntawm aggregation 3 (los yog ib tug 3 theem) raws li ib tug khoom, ib tug kua los yog ib tug gaseous lub xeev. Yog li ntawd, nws yog suav tias yog ib tug ua kev tshuaj tiv thaiv yog tias cov tshuaj nkag mus rau hauv nws, yog nyob rau hauv sib txawv xeev ntawm aggregation, piv txwv li:

• gas + kua
• gas + khoom
• kua + khoom.

Yog hais tias cov tshuaj uas hnov mob nrog txhua lwm yam muaj nyob rau hauv tib lub xeev ntawm aggregation, xws tshua yog hu ua homogeneous. Lo lus kuj txhais tau ua los ntawm cov neeg Greek, "gomos" - tib yam, zoo sib xws.

Homogeneous thiab heterogeneous tshua kheev tshwm sim nyob rau hauv peb lub neej. Xav txog, piv txwv li, cov tshuaj tiv thaiv cov ntoo combustion. Taws - yog, thiab loj, ib tug tshuaj tshuaj ntawm cov organic keeb kwm - cellulose. Tsis muaj ib tug tsis ntseeg, tus ntoo - ib yam khoom uas yog nyob rau hauv ib tug khoom hauv lub xeev. Lawv hlawv vim qhov kev txiav txim ntawm oxygen. Pa - yog ib cov roj. Raws li ib tug tshwm sim, lub combustion cov tshuaj tiv thaiv ntawm taws tsim thee, carbon dioxide thiab dej. Combustion ntawm ntoo raws li hlawv cawv - ib tug ua kev tshuaj tiv thaiv. Piv txwv yuav raug coj los mus infinity.

1) Rusting hlau. Firstly, ib yam tshuaj cov tshuaj tiv thaiv, vim hais tias cov kev tshwm sim ntawm tus tshiab yam khoom uas yog tsim nyob rau ntawm hlau - xeb hlau hydroxide (III). Secondly, nws yog ib tug ua kev txheej txheem, txij thaum lub hlau - yog ib tug khoom thiab cov dej thiab cua oxygen, uas tuaj nyob rau hauv tus rusting - yog kua thiab gas feem. Qhov no txoj kev muaj peev xwm yuav sau los ntawm cov nram qab no cov tshuaj tiv thaiv kab zauv :

Fe (tv.) + H2O (g.) + O2 (g) = Fe (OH) 3 (huab.)

2) quenching ntawm vinegar dej qab zib. Muaj ntau tus poj niam kuj siv tau qhov no tshuaj cov tshuaj tiv thaiv rau qhov kev npaj ntawm ua khob noom cookie lush. Thaum zoo li no yog coj dej qab zib khoom NaHCO3 rau hauv cov hmoov daim ntawv thiab ib tug 3% daws teeb meem ntawm acetic acid CH3COOH, yog li ntawd, nws kuj yog ib tug ua kev txheej txheem, txij li thaum ob interacting tshuaj nyob rau hauv sib txawv xeev ntawm aggregation. Qhov no tus txheej txheem no piav los ntawm tus kab zauv:

NaHCO3 + CH3COOH = CH3COONa + H2O + CO2

Nco ntsoov tias ntawm no thiab cov tshuaj tiv thaiv cov khoom uas nyob rau hauv sib txawv xeev ntawm aggregation - sodium acetate thiab dej CH3COONa + H2O - yog kua thiab CO2 - yog cov pa roj carbon dioxide.

3) Blackening bronze monuments los yog diav nyob rau hauv ambient tej yam kev mob - yog tseem ua kev tshua.

Kuv vam thiab cia siab tias tam sim no no lub sij hawm tsis ua rau koj tej teeb meem. Thiab yog hais tias koj tseem muaj lus nug, tsis txhob yuav tub nkeeg mus qhib ib phau ntawv nyob rau hauv Science News for KIDS rau qib 8 thiab rov hais dua cov ntaub ntawv them dua. Nws yeej tsis mob, nws tsis yog rau ib yam dab tsi uas lub Lavxias teb sab paj lug hais tias: "Repetition - Xyaum ua zoo meej!"