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Materie, meting en reaksies

Materie en meting

Opvoeder afdeling


Voorbeelde van fisiese verandering : ‘n pan wat verhit word; tee wat afkoel

Voorbeelde van chemiese verandering: vuurhoutjie wat brand; brood wat rooster


  • Ja, dit smaak anders, effens na brand
  • Ja, dit het swart en poeieragtig geword
  • Chemiese verandering : Dit is permanent, die chemiese reaksie het die suiker in koolstof verander.

Leerder afdeling


Aktiwiteit: om fisiese en chemiese veranderinge in stowwe to ondersoek en te kan bespreek [lu 2.3]

Mense gebruik verskillende natuurlike stowwe en verander dit in iets anders. Stowwe word met ander gemeng, verhit, geskei, opgelos of met elektrisiteit behandel ten einde die verandering teweeg te bring. Sommige veranderinge is egter nie blywend nie, maar ander is weer nie omkeerbaar nie. Ons onderskei tussen fisiese en chemiese verandering.

Fisiese Verandering

Wanneer versuikerde heuning in ‘n pot verhit word, raak dit weer vloeibaar. Sodra dit egter weer afkoel en blootgestel word aan lug, versuiker dit weer. Geen nuwe stowwe is gevorm nie, die eienskappe is nog presies dieselfde en ons noem hierdie verandering ‘n fisiese verandering. In die vorige eksperiment het die oranje kwikoksied weer swart geword nadat dit afgekoel het (fisiese verandering).

Chemiese Verandering

Wanneer rou pannekoekdeeg in warm olie gegooi word, gebeur daar iets. Die voorkoms van die deeg verander. Dit is nie meer loperig nie en word hard. Die verandering wat plaasgevind het, is permanent. Veranderings wat permanent is en wat iets nuuts voortbring, word chemiese veranderings genoem. Die nuwe stof se eienskappe verskil van die oorspronklike stof s’n. Die kwikoksied het ook ‘n chemiese verandering ondergaan toe dit ontbind het in kwik en suurstof.

Noem nog twee voorbeelde van fisiese en twee voorbeelde van chemiese veranderinge.





Probeer die volgende:

Bring malvalekkers skool toe. Sit dit op die punt van ‘n vurk en hou dit oor ‘n vlam. Beantwoord dan die volgende vrae.

  • Het die smaak verander nadat dit verhit is? Wag totdat dit afkoel voordat jy proe.
  • Het die voorkoms verander? Beskryf die verandering.
  • Is dit ‘n chemiese of ‘n fisiese verandering? Motiveer jou bevinding.






Leeruitkomste 2: Die leerder ken, interpreteer en pas wetenskaplike, tegnologiese en omgewingskennis toe.

Assesseringstandaard 2.3: Dit is duidelik wanneer die leerder inligting interpreteer: identifiseer kernidees in die teks, vind patrone in aangetekende data en maak gevolgtrekkings uit inligting in verskeie vorme (prente, diagramme, ens.).

Questions & Answers

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are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
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That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
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In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
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Source:  OpenStax, Natuurwetenskappe graad 7. OpenStax CNX. Sep 16, 2009 Download for free at http://cnx.org/content/col11078/1.1
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