RbOH is a strong base that dissociates completely and HCl is a strong acid that too dissociates completely. the complete reaction between the acid and base is; RbOH + HCl ---> RbCl + H₂O stoichiometry of acid to base is 1:1 At neutralisation point H⁺ mol = OH⁻ mol mol = molarity x volume if Ma - molarity of acid and Va - volume of acid reacted Mb - molarity of base and Vb - volume of base reacted Ma x Va = Mb x Vb 0.5 M x 52.8 mL = Mb x 60.0 mL Mb = 0.44 M molarity of base - 0.44 M
Out of the options, the best indicator is a color change since it is the only one that can't really be blamed on a physical change. you will eventually notice that during qualitative labs and some quantitative labs, usually the thing that you are looking for is either color change or the production of a precipitate to indicate the presence of a chemical reaction
