Other contributors have said "Does metal change the color of litmus paper red?" is the same question as "What does not change litmus paper color?" If you believe that these are not asking the same thing and should be answered differently, click here
Because it canges color if it is a base or a acid, I think its blue for base and red for acid Blue at pH > 8 and red at pH < 5.5 ; In between the color change is not very indicative.
Litmus contains organic chemicals that have a particular colour (some kind of red) when protonated - that is, in acidic conditions - but a different colour (blue) when in basic conditions or when...