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Why is glass rod used in decanting?

  1. Jun 24, 2014 #1
    I always see in many books and articles. Glass rod is used for decantation. Why should we not pour the liquid just directly. I asked my chemistry teacher. She told me to experiment myself by decanting two identical heterogenous mixtures, one using a rod and other without one.

    Please tell me any significance of glass rod other than to avoid any spills?
     
  2. jcsd
  3. Jun 24, 2014 #2

    SteamKing

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    If done properly, the liquid being poured will adhere to the glass rod and flow along it into the receiving container, eliminating spillage and spatter. For most liquids, it's not a problem if a little spatter is encountered, but if you are pouring a highly corrosive chemical, like concentrated sulfuric acid, a little spatter could be very dangerous. That's the way I've looked at it.
     
  4. Jun 24, 2014 #3

    Borek

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    And I don't think there is more to it.
     
  5. Jun 24, 2014 #4
    Thank you everybody now I guess why my teacher told me to experiment myself. Because I asked her whether it is to avoid spillage She gave no reply and asked me to experiment my-self.
     
  6. Jun 24, 2014 #5

    SteamKing

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    Well, use a liquid which is not dangerous if you happen to get some on yourself or others.
     
  7. Jun 25, 2014 #6
    I experimented it for decanting a mixture of ##H_2O## and ##CaCO_3##. It just helped me pour the liquid uniformly and slowly without spilling.
     
  8. Jun 25, 2014 #7

    sophiecentaur

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    AS well s the safety aspect, there is a matter of accuracy when you need to measure the quantities involved. (i.e. Splashes will lose some of the reactants.
     
  9. Jun 25, 2014 #8
    Plastic gets worn and metals may react. Glass is smooth so retains (wastes) little of the chemicals, is easily cleaned, is durable, is brittle so will not bend and is very obvious when it's no good anymore.

    And then there is that splish splash song from the 50's that I just planted in your brain for next three hours. You don't want to suddenly have to take a bath. In front of everyone in the Lab. You will be hearing about it the rest of your life. Or until you win some prestigious award.
     
  10. Jun 26, 2014 #9
    1. lol i ain't in us or any other countries where hollywood is famous.
    2. I born at 2000 only and not alive in the 50s.
    3. I experimented it in my house rather than a lab. I am not sure the school will allow a 9th grader to perform experiments on his wish in its lab.

    BTw thanks for creating a humour
     
  11. Jun 26, 2014 #10

    sophiecentaur

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    I got out of the bath, put my feet on the floor,
    put my towel around me and walked out of the door . . . . .
    Splish splash, I jumped back into the bath
    'cos how was I to know there was a chemical experiment going on?
    et. etc.
     
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