A Short Note On Sodium Hydroxide As An Indicator Of Acid Base Reactions
C_20 H_14 O_(4 (aq))+46 NaOH_((aq))→46 Na_( (aq))^++20 H_2 CO_(2 (aq))+10 H_2 O_((l)).
Phenolphthalein and sodium hydroxide react to form carbonous acid, water, and Na+ ions. This reaction is a neutralization reaction, where phenolphthalein, a weak acid, reacts with a strong base, sodium hydroxide. When phenolphthalein is put into a basic solution, it turns pink. The phenolphthalein ion is pink, and when a base and phenolphthalein are combined, more H+ ions are removed and the equilibrium moves to the right. At the endpoint of a reaction, all of the H+ ions have reacted and been neutralized, so the phenolphthalein ionizes resulting in a pink solution. The phenolphthalein used in this lab was the deprotonated phenolate form, In2−, because the solution turned pink.
A: The reaction between potassium hydrogen phthalate and sodium hydroxide is a neutralization reaction. The equation is KHP(aq) + NaOH(aq) KNaP(aq) + H2O(l). Standards are often used in chemistry. Standards have a known concentration of a substance and can be used to determine other information. These materials can be used as a reference to compare to other substances or to determine unknown concentrations. There are two types of standards: primary and secondary. Primary standards are often used in titrations. Primary standards are very pure and stable, and normally have a high molecular weight. They…