A pH strip is a strip which helps in determining whether a solution is acidic or basic in nature.
That is, if a solution is acidic in nature then a pH strip will change from blue to red. Whereas when a solution is basic in nature then a pH strip will change from red to blue.
Thus, we can conclude that statement molecules in the paper react differently with hydronium and hydroxide ions, best describes how a pH test strip works.
Molecules in the paper react differently with Hydronium and Hydroxide.
pH paper deals with acidity and basicity of something. You are correct in thinking that A is the answer. Always go with your gut. don't be like me when I was in college who always second guessed my answers. Good luck with chemistry.
Ligands are small molecules that transmit signals in between or within cells. Ligands exert their effects by binding to cellular proteins called receptors.
