Make Red Litmus Paper

Things you need 
red cabbage
coffee filter
microwave

Step 1:

 cut the red cabbage into pieces then microwave them for about 4min 

Step 2:

The final step is to put the filter paper on the heated red cabbage and let the filter paper suck up the juice. Know you are done

if you put baking soda on it, it turns green or yellow that means it is a base and if you put lemon juice on it, it turns pink that means it is a acid