Vinegar, iodine, PR, and PH we did iodine to see if it had starch. We did vinegar to see if it would fizz. We did PH to see if it had litmus paper. We did PR to see if it's and acid or a base.
We mixed all the powders together and all the liquids to see if it would fizz and it didn't but it did turn purple.
I learned that if you cross contaminate it could ruin your whole test because it'll turn different colors instead of the ones it is suppose to be.