True or false. a change of color is a sign that a chemical reaction is taking place.

True, it shows that a reactant (s) have changed propertirs and hense there must be a new compound to cause the colour change.

Answerchemical energy;

The question is incomplete. complete question is attached belowanswer: correct answer is option b  i.e.  solid particles  reason: filter paper has small pores, through which smaller particles can pass through. however, solid particles  have relatively larger size. hence, they are least likely to pass through.