acid and bases (1 Viewer)

zeinab7691

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i have an open ended investigation assesment task to do and its about home made indicators. we have to find a home made indicator and test it on a base or an acid n proove that it works. Any ideas of home made indicators i can use. ive herd of red cabbage?
 

me121

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zeinab7691 said:
i have an open ended investigation assesment task to do and its about home made indicators. we have to find a home made indicator and test it on a base or an acid n proove that it works. Any ideas of home made indicators i can use. ive herd of red cabbage?
just grind up red cabbage, extract the juice, add a bit of water, then wolla, you have your own indicator. you can test it by observing the colour change in substances like vinegar, detergent, etc, etc...
 

midifile

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Red cabbage works really well - just cut it up, boil it in water and once the water turns purple extract it using a pipette and tests substances. I think that tea also works (but not very well) but if you have to test more than one substance you can use that too.
 

munchiecrunchie

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other stuff that also works: beetroot and colourful flowers (eg hydrangeas, roses)

btw the cabbage stinks - i prefer the roses coz they leave a nice smell.
 

minijumbuk

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HSC Online website said:
  • Perform an investigation like the one described below. You may need to make modifications to your planned procedure as you go. Identify and use safe work practices during your investigation, being particularly careful with heating equipment and any hot solutions.
Making indicators
  1. Collect some coloured plant material such as flowers or a few leaves of red cabbage. Select the coloured parts and cut into small pieces.
  2. Place them in a small saucepan or microwavable dish and add enough water to just cover the pieces.
  3. Boil gently in the saucepan for 10 minutes (or microwave in the dish for 5 minutes).
  4. Cool the mixture.
  5. Pour off the liquid, leaving the solid behind.
  6. Record the colour of the solution.
  7. Add some of the solution to an equal volume of vinegar, shake and record the natural indicator colour in an acidic substance.
  8. Add some of the solution to sodium bicarbonate (baking soda), shake and record the natural indicator colour in a basic substance.
  9. If you obtained different colours for a solution with the acidic substance and with the basic substance, then you have prepared an acid-base indicator solution. This solution will give one colour in contact with an acidic substance and another colour with a basic substance.
Hope it helps =)
Here's the main website, it has a plenty of materials to guide you through some courses:
HSC Online
 

zeinab7691

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Thanksss heaps guys. It really helped. Now i have to perform the experiment for 3 indicators on many bases and acids.. hahahha that should be *very* fun.. lol sarcasm.. :):) thanksss agen
 

Undermyskin

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Just grind the cabbage then filter. Boiling it takes heaps of time.
 

miz2nv

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need help 4 chem we hve 2 make a model showing
hydrochloric acid and acetic acid any help with how they will look

please help
 

Gibbatron

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need help 4 chem we hve 2 make a model showing
hydrochloric acid and acetic acid any help with how they will look

please help
Hydrochloric acid:

H -- Cl

Acetic Acid:
H
|
H -- C -- C -- O -- O -- H
|
H
 

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