PH, biology videos

Our biology teacher, Cecilia Adem, gave us two videos to watch. Here are my summaries of them:

  • First video:

What does the PH shows?

The PH shows you how acidic a substance is. The ph scale is from 1-14. If the solution is above 7, it is a base. If it is lower than 7 the substance is acidic and if it is 7 it is neutral. When litmus turned from red to blue it indicates a change in solution from an acid to a base.

Its necessary to know the pH value of the substances.

Whats the difference between an acid and a base?
The difference between an acid and a base is that a base accepts a proton that is being given from an acid.

  • Second Video:

To tell if a substance is acid using pH paper, the paper will changen color to a more yellowish color. But if you want to know using red cabagge the color will change red. They are Ionic compounds,
If you use pH paper to tell if it is a base, the paper will change to a purpley color and if you use red cabbage the color will change into a pale blue or green. They are solutions that are not neutral or acid, and Ionic Compounds.

The strength of the bases and the acids is dependent on the concentration of Hydrogen and Hydroxide Ions.