Year 12 prac

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Jazz
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Year 12 prac

Post by Jazz »

Year 12 last chemistry class. This year I made one for myself
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Cheers Jazz
JelJane
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Re: Year 12 prac

Post by JelJane »

So pretty 8-) ! Gotta love chemistry - do the kids get to take them home?
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nickyw
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Re: Year 12 prac

Post by nickyw »

What is it Jazz?
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Lyn
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Re: Year 12 prac

Post by Lyn »

It's a Tollen's silver mirror practical. Do a search on our lab tech site for Tollen's reagent and you will find a method for the prac and safety notes to follow.
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Jazz
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Re: Year 12 prac

Post by Jazz »

You are right Lyn it is Tollen's silver mirror. We do this prac with year 12 (last chemistry leson) and they can keep it as a souvenir
Cheers Jazz
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Jazz
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Re: Year 12 prac

Post by Jazz »

Honey I shrunk our cups
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Cheers Jazz
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Lyn
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Re: Year 12 prac

Post by Lyn »

Alright, don't leave us guessing. What did you do?
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Jazz
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Re: Year 12 prac

Post by Jazz »

Before and after
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Cheers Jazz
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Jazz
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Re: Year 12 prac

Post by Jazz »

Shrinking Styrofoam cups 5 min in pressure cooker
Shrinking bag 5 sec in microwave

Difficulties are made to be overcome
Cheers Jazz
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nickykinz
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Re: Year 12 prac

Post by nickykinz »

Would you be able to give us the specifics of what you for the Tollen's one? Are they small conicals, and do you need to swirl the solution around or does it work its way up the glass?
Nicky
;)
St Augustine's College
Augustine Heights, QLD 4300
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kimmy
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Re: Year 12 prac

Post by kimmy »

Just had a look at this on you tube looks great. :w00t:
Recipe/instructions that you all use please. [-o<
thanks
KIMMY
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Jazz
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Re: Year 12 prac

Post by Jazz »

Silver Mirror

1L of of silver nitrate solution (17g AgNO3 dissolved in in 1L of deionised water)
500 mL of potassium hydroxide solution (22.4g KOH dissolved in 500mL of deionised water)
100 mL glucose solution (4.4g glucose in 100 mL of deionised water)

400mL x 880 ammonia (approx 15M) in fume cupboard with a dropper (4 x dropper bottles please)

Tollen's reagent contains ammonium hydroxide which is corrosive and harmful if you swallow it. It can also cause damage if splashed into the eyes. If spilt upon the skin, the silver ions in Tollen's solution may, over the course of one or two days, produce a black stain on the skin. This is not likely to be harmful, nor will it be permanent, but may be unsightly. There is a small risk of forming explosive fulminating silver, if Tollen's reagent is left unused for a period of time. To avoid this, neutralise unused reagent with a little nitric acid and discard. Do NOT prepare Tollens Reagent
Disposal: Small amounts can be neutralised with nitric acid (test with pH paper) and then flushed down the sink. Do not store unwanted reagent for long periods. After the demonstration, do NOT save the silver solution in a silver residues container. The solution must be disposed of down the sink with plenty of cold water within 30 minutes of mixing at the start of the demonstration. This is to avoid any chance of the formation of a deposit of silver fulminate, a dangerously explosive substance.

To avoid washing up (bellow) we use only new 100 mL flasks ($1.5 e.a) or girls can bring their own
14 x small clean conical flasks.with rubber bungs/stoppers - these must be cleaned with soapy water and brush and then rinsed and then cleaned with conc nitric acid, finally rinsed out several times with deionised water. - thorough cleaning is essential for the silver mirror to form.
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Cheers Jazz
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kimmy
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Re: Year 12 prac

Post by kimmy »

thanks for that.


:clap3: :clap3: :clap3:
tuesday
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Tollens reagent

Post by tuesday »

HI All,
Has anyone had to make Tollens reagent and if so what is your recipe please . Need it for our year 11 chemistry, I know what chemicals go into it but not sure on the amounts of each.
Thank you in advance
karend
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Re: Tollens reagent

Post by karend »

Never had to make it but found this recipe on file:-
A few drops of dilute NaOH is added to aqueous AgNO3. Aqueous ammonia is added until all of the brown silver (I) oxide is dissolved. At this point mixture will be clear.
Hope this helps tuesday
tuesday
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Re: Tollens reagent

Post by tuesday »

That's fantastic, thank you
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Lyn
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Re: Tollens reagent

Post by Lyn »

Please do a search for Tollens reagent on this site. There are two very good outlines for this prac. One by Jazz and another by Labbie. Step by step instructions with chemicals and procedure. I don't know how to link up your request with the information provided by these two.
tuesday
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Re: Tollens reagent

Post by tuesday »

Iv'e tried to do a search and the only thing that came up was how to dispose it. I'll try again
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Kathy
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Re: Tollens reagent

Post by Kathy »

Try searching for 'silver mirror'
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Lyn
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Re: Tollens reagent

Post by Lyn »

The "silver mirror" will bring up Jazz's explanation and Re: Tollens reagent should bring up another by NTrivedi. Sorry, it wasn't Labbie's post, it was the post underneath that one.
Have just tried to follow my own directions and found that once you get the search page for Re:Tollens reagent for some reason you need to click onto Labbies post which then opens up to show the NTrevidi post. Where is that emoticon for tearing ones hair out in frustration. Has anyone else come up against this? Can anyone do a cut and paste to put them in the one spot? Please.
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