Dab tsi hloov xim ntawm litmus ntawv?
Dab tsi hloov xim ntawm litmus ntawv?

Video: Dab tsi hloov xim ntawm litmus ntawv?

Video: Dab tsi hloov xim ntawm litmus ntawv?
Video: yog hmoov dab tsi. Zoo Xyooj (cover) 2024, Hlis ntuj nqeg
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Litmus yog ib qho tsis muaj zog acidic, xim organic dye. Raws li nws ib puag ncig kev hloov los ntawm acid ( pH <7) rau hauv paus ( pH > 7), lub molecule kev hloov los ntawm protonated acid mus rau ionized ntsev. Nws xim kuj kev hloov ntawm liab mus xiav. (Qhov tiag pH thaj tsam rau qhov no xim hloov los ntawm 4.5 txog 8.3.)

Ib sab ntawm no, dab tsi hloov xim ntawm litmus ntawv?

Xiav ntawv litmus hloov liab nyob rau hauv acidic tej yam kev mob thiab liab ntawv litmus hloov xiav nyob rau hauv tej yam kev mob los yog alkaline, nrog rau xim hloov tshwm sim tshaj pH ntau yam 4.5-8.3 ntawm 25 ° C (77 ° F). Nruab nrab ntawv litmus yog ntshav. Piv txwv li, ammonia gas, uas yog alkaline, tig liab ntawv litmus xiav.

Tsis tas li ntawd, vim li cas cov kua qaub hloov xim ntawm litmus ntawv? Nws yog vim 7-hydroxyphenoxazone. Thaum raug kua qaub hauv qab pH 4.5, lub molecule zoo li cov duab hauv qab no thiab qhov no muab ntawv litmus nws red xim . Lub xub ntiag ntawm kua qaub ua rau litmus tig liab thaum muaj lub hauv paus (alkali) tig litmus xiav.

Ntawm no, pH ntawv hloov xim li cas?

Yog vim li cas Xim hloov Qhov no pH ntawv hloov xim nyob rau hauv txawv pH kev daws teeb meem vim yog cov tshuaj flavin, uas yog cov xim muaj nyob rau hauv liab cabbage. Nyob rau hauv lub xub ntiag ntawm ib tug acidic tov, nws tig liab. Nyob rau hauv lub xub ntiag ntawm ib tug yooj yim tov, nws puv greenish.

Dab tsi ua rau cov ntsuas hloov xim?

Cov xim hloov ib pH qhov taw qhia yog ua rau los ntawm dissociation ntawm H+ ion los ntawm qhov taw qhia nws tus kheej. Nco qab tias pH ntsuas tsis tsuas yog ntuj dyes tab sis kuj tsis muaj zog acids. Lub dissociation ntawm qaug zog acid qhov taw qhia ua rau kev daws rau hloov xim.

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