Video: Lub mole tau muab tau li cas?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Avogadro tus lej, tus naj npawb ntawm cov khoom hauv a mole , tuaj yeem txiav txim siab los ntawm thawj "suav" tus naj npawb ntawm atoms hauv qhov chaw me me thiab tom qab ntawd scaling mus nrhiav tus naj npawb ntawm cov khoom uas yuav muaj huab hwm coj sib npaug ntawm atomic lossis molecular hnyav hauv grams.
Ib yam li ib tug yuav nug, lub tswvyim mole tau tsim li cas?
Keeb kwm ntawm lub mole yog intertwined nrog cov molecular mass, atomic mass units, Avogadro tooj. Thawj lub rooj ntawm tus qauv atomic hnyav (atomic mass) tau luam tawm los ntawm John Dalton (1766-1844) nyob rau hauv 1805, raws li ib tug system nyob rau hauv uas tus txheeb ze atomic mass ntawm hydrogen tau txhais ua 1.
Ib tug kuj yuav nug, thaum twg yog tus mole nrhiav tau? Feem ntau, ib qho mole ntawm tej yam khoom muaj Avogadro tus naj npawb ntawm molecules los yog atoms ntawm cov khoom. Qhov kev sib raug zoo no yog thawj zaug nrhiav pom los ntawm Amadeo Avogadro (1776-1858) thiab nws tau txais credit rau qhov no tom qab nws tuag.
Khaws qhov no hauv kev xav, dab tsi yog qhov mole raws li?
Zoo li tag nrho cov units, a mole yuav tsum yog nyob ntawm ib yam dab tsi rov tsim dua. A mole yog qhov ntau ntawm txhua yam uas muaj tib tus lej ntawm cov khoom pom hauv 12.000 grams carbon-12. Tus lej ntawd yog Avogadro's Number, uas yog kwv yees li 6.02x10.23. 1? A mole carbon atoms yog 6.02x1023 carbon atoms.
Vim li cas mole hu ua mole hauv chemistry?
Cov mole yog ib chav tsev siv nyob rau hauv chemistry uas yog sib npaug rau Avogadro tus lej. Nws yog tus naj npawb ntawm carbon atoms hauv 12 grams ntawm cov isotope carbon-12. Lo lus mole los ntawm lo lus molecule. Cov mole feem ntau yog siv los hloov ntawm cov lej ntawm cov atoms thiab cov molecules mus rau gram pawg.
Pom zoo:
Yuav ua li cas koj pom lub kaum sab xis nruab nrab muab qhov chaw thiab lub vojvoog ntawm ib lub sector?
Kev txiav txim siab Central Angle Los ntawm Sector Area (πr2) × (central angle in degrees ÷ 360 degrees) = sector area. Yog hais tias lub hauv paus lub kaum sab xis ntsuas nyob rau hauv radians, lub mis hloov mus ua: sector cheeb tsam = r2 × (central kaum hauv radians ÷ 2). (θ ÷ 360 degree) × πr2. (52.3 ÷ 100π) × 360. (52.3 ÷ 314) × 360
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