A simple experiment to determine an unknown powder

AI Thread Summary
To identify an unknown white powder among six possible substances, a series of chemical tests can be conducted. Reacting the powder with acetic acid will indicate if it is a carbonate, as it will produce bubbles from CO2. The addition of silver nitrate solution can confirm the presence of sodium chloride, resulting in a cloudy white precipitate. Using phenolphthalein can help determine if the powder is basic, as it turns pink in basic conditions. The solubility of the powder can also be assessed by observing its reaction with spent acetic acid.
Zaros
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Homework Statement


You are given a white powder and it could be one of six substances: calcium carbonate, calcium sulfate, sodium hydrogen carbonate, sodium carbonate, sodium chloride and sodium hydroxide. Determine the unknown sample.
Materials: White powder (5g)
Phenolphthalein
Silver nitrate solution
Acetic acid

The Attempt at a Solution


React with acetic acid if it is a carbonate it will bubble (CO2 formed)

React with the silver nitrate solution if it is sodium chloride it will form a cloudy white solution:
AgNO3 + NaCl → AgCl(s) + NaNo3

Now the phenolphthalein changes from colourless to pink when the pH goes above 8.2 so I assume there is some way to find out which one using basic acidic but this is where I start to have trouble as I am unsure what other experiments to do.
Thanks for the help
 
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What is the solubility of silver carbonate? Silver sulfate?
 
I'd like to first use phenolphthalein to check whether the given salt is basic or not. It will really classify them in broad sense.

Check how many are basic enough to give positive tests with phenolphthalein?
 
Zaros said:
React with acetic acid if it is a carbonate it will bubble (CO2 formed)
If you continue to add powder to a sample of acetic acid after bubbling ceases, you will be able to see whether that powder is soluble (i.e., forms an aqueous solution).

You aren't provided with water to test the powders for solubility, so use some spent acid as your water source.
 
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