John has three bottle of mineral acid but does not know which is which since he did not label the bottles before filling them. Suggest a method to which could be used to identify the acids.
Do you have a list of the mineral acids? It would help since there are more than three in practice. The usual ones are HCl, H2SO4, HNO3 but there are many more.
You can read more about them here.
http://en.wikipedia.org/wiki/Mineral_acid
Here is a simple solubility chart which should help you identify them. For example, to test for sulfate (if H2SO4), add BaCl2 and a white ppt insoluble in HNO3 denotes H2SO4. AgNO3 gives a white ppt of AgCl with HCl. ETC.
http://www.files.chem.vt.edu/RVGS/ACT/notes/solubility_rules.html
To identify the mineral acids in John's bottles, he can use a process called acid-base titration. Acid-base titration is a technique used to determine the concentration of an acid (or a base) in a solution by adding a measured amount of a known base (or acid) to the solution of the unknown acid (or base) until neutralization occurs.
Here's a step-by-step method John can use to identify the acids:
1. Gather the necessary materials: distilled water, a burette, a conical flask, a pH indicator solution (such as phenolphthalein), and a standardized solution of a strong base (such as sodium hydroxide).
2. Start by preparing a diluted sample of each acid in separate containers. This can be done by adding a known volume of distilled water to each bottle of acid, resulting in a diluted solution.
3. Fill the burette with the standardized base solution (sodium hydroxide).
4. Take the first diluted acid sample and transfer it into the conical flask. Add a few drops of the pH indicator solution to the flask. The indicator will change color when the solution becomes neutral.
5. Slowly add the standardized base solution from the burette to the conical flask while continuously stirring the mixture.
6. Watch for a color change in the solution. When the color change occurs, stop adding the base solution and note the volume of the base solution used.
7. Rinse the conical flask and repeat the process for the other two diluted acid samples, using a fresh portion of the indicator solution for each sample.
8. Compare the volumes of base solution needed to reach the color change for each acid sample. The acid sample that required the least amount of base solution to achieve neutralization will have the highest concentration of acid.
By following this method, John can identify the acids in his bottles based on their different reaction rates with the standardized base solution during acid-base titration.