1. Unit 11 Acids and Bases

4. Basic Acidic Neutral H+ H+ H+ OH- OH- OH- Solution Solution Solution Which solution is Acidic? Basic? Neutral???

25. Balance the final equation! H 2 S + Ca(OH) 2  CaS + H 2 O 1 Ca 1 1 S 1 4 H 2 2 O 1 H 2 S + Ca(OH) 2  CaS + 2 H 2 O

26. Neutralization Reactions Try another example: Acid + Base  Salt + Water H 2 SO 4 + NaOH  Na 2 SO 4 + H 2 O 1 Na 2 1 SO 4 1 3 H 2 1 O 1 H 2 SO 4 + 2 NaOH  Na 2 SO 4 + 2 H 2 O

27. Take it one step further… Sulfurous acid and sodium hydroxide yields sodium sulfite and water. H 2 SO 3 + NaOH  Na 2 SO 3 + H 2 O 1 Na 2 1 SO 3 1 3 H 2 1 O 1 H 2 SO 3 + 2NaOH  Na 2 SO 3 + 2H 2 O

30. pH Indicators 3) Bromthymol Blue – Add a few drops of bromthymol blue to the substance. If the blue color turns to yellow  Acid If the blue color stays blue  Base 4) Phenolphthalein – Add a few drops of phenolphthalein to the substance. If the clear liquid turns to pink  Base If the clear liquid remains clear  Acid