Neutralization Reactions Section 21.1

Neutralization Reactions Acid + Base  Water + salt Hydronium ions + hydroxide ions  water + water H3O+ + OH-  H2O + H2O Examples: HCl + NaOH  H2O + NaCl H2SO4 + 2KOH  2H2O + K2SO4 All neutralization reactions are double displacement reactions

Titrations Standard Solution Titration End Point The solution of known concentration Titration The process of a specific amount of a known solution to an unknown solution to determine the molarity of the unknown solution End Point When the indicator shows that neutralization has occurred

Example graph of end point

Sample Problem A 25mL solution of H2SO4 is completely neutralized by 18mL of 1.0 M NaOH using phenolphthalein as an indicator. What is the concentration of the H2SO4 solution? H2SO4 + 2NaOH  2H2O + Na2SO4 25mL H2SO4 1L H2SO4 1.0 mol H2SO4 2 mol NaOH 1000mL = 0.36M NaOH 1000mL 1 L H2SO4 1 mol H2SO4 18mL NaOH 1L Use stoichiometry to go from mL of your known solution to find Molarity (mol/L) of your unknown solution