False Positives

What is a false positive?

A result that suggests that a particular ion is present when it actually isn't.

When can false positives happen?

If there are ions present that will interfere with the test you're carrying out.

What can you do to prevent false positives?

Add a substance to your sample to remove problematic ions

What do you need to be careful about?

What substances you add during the test as it's important not to add any ions that will lead to false positives

What's the order of testing you should do?

Test for carbonates, test for sulfates, test for halides.