In section C you did some titrations of HCl with NaOH, using BTB as an indicator. What is observed at the endpoint, and what is the overall and net ionic equation?
HCl(aq) + NaOH(aq) → NaCl (aq) + H₂O (l)
H⁺(aq) + OH⁻(aq)→H₂O(l)
Endpoint: yellow color → dark blue