Comments on: Chemistry Phenomenon – Limestone In Action!

By: Kate Saito

Kate Saito — Thu, 29 Jul 2010 08:38:40 +0000

Hi sir!

Can i ask for a simple ivestigatory project and a chemistry related phenomena?
thanks!

By: John

John — Sun, 25 Jul 2010 16:14:50 +0000

Hi, I know that Zinc Oxide turns from white to yellow when heated and then turn from yellow to white when cooled down. Does the same thing occur for Calcium Oxide? I think that there is no colour change as both calcium carbonate and calcium oxide are white in colour.

On a side note, I would like to know how to carry out tests on an insoluble solid. For example, Silver Chloride. It cannot dissociate in water so how do I go about testing for such solids during a SPA test?

Thanks a lot.

By: sean

sean — Wed, 05 May 2010 14:52:26 +0000

Hi Aiden,

I suppose you meant “Limestone is Calcium Carbonate”.

You wont see “effervescence” since there is not liquid/solution.

Effervescence is equivalent to “bubbling effect”. Calcium carbonate is a solid and upon thermal decomposition, you wont see effervescence.

Observation: Since Calcium Carbonate becomes Calcium Oxide, check if there is any colour change to the solid present in the beaker. Think about it.

To Your Academic Success in Chemistry,
Sean
Master Trainer & Author

By: Aiden

Aiden — Wed, 10 Mar 2010 06:20:42 +0000

1) Limewater is basically Calcium carbonate, and when calcium carbonate experiences thermal decomposition, the products are Calcium oxide and Carbon dioxide.

2)A white solid will be formed and there will be effervescense because of the release of carbon dioxide.

By: O Level Chemistry Questions & Answers – Summary by SimpleChemConcepts

Wed, 03 Feb 2010 16:43:02 +0000

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