1. Neutralization Reactions Section 21.1

2. 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

3. Titrations • Standard Solution • 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

4. Example graph of end point

5. 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