Litmus Paper
Red litmus paper
Red litmus paper is red and when it is dipped in a acid it stays red and when dipped in a base it turns blue.
Blue Litmus Paper:
Blue litmus paper is blue and when it is dipped in a acid it turns red and when dipped in a base it stays blue.
pH paper
pH paper is used for determining whether a substance is an acid or base. To do this you use the pH scale which goes from 1-14. If the pH is less than 7 it is a acid and if it above 7 then it is a base. The only exception is when the pH scale reads 7 which means that the substance is neutral. You can tell the pH of said solution by looking at the color that it corresponds with. If you look at the picture, you can see the color correspondence to the pH
Phenolphthalein
When using phenolphthalein, drop some of it into the solution you are testing for neutralization. After placing phenolphthalein in the solution, if the color is clear, then that is an indication that the solution is an acid. If the color turns magenta, then that is an indication that the solution is a base.
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