Mammoth Memory

Testing acids and alkalis using universal indicator

Acids turn red when an indicator is added.

person having a bath in acid

You would try to kill a zombie with a bath of acid, which would turn red if you did! (Acidic solutions turn universal indicator red). 

 

A neutral solution (like water) will turn green.

image of a chameleon with a gear shifter on its body

Think of a gear stick sticking out of a chameleon; when the gear stick is in the neutral position, the chameleon turns green

 

An alkaline solution will turn universal indicator blue or purple

 Dirty toilet being cleaned with bleach

Bleach (an alkaline) comes in a blue bottle.

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