Acids/Bases and the pH Scale

Properties of Acids and Bases Taste sour Taste Bitter Turns blue litmus paper red Turns red litmus paper blue Reacts with metals Produces Hydroxide ions (OH-) in water Produces Hydrogen ions (H+) in water Feels Slippery Reacts with carbonates to produce CO2 gas

Acid, Base, Neutral, or Both (Acid and Base) 1. pH of 7 _______________________________ 2. ammonia _____________________________ 3. fluid in the stomach ____________________ 4. produces hydrogen gas __________________ 5. NaOH or KOH _________________________ 6. saliva in the mouth ______________________ 7. conduct electricity ______________________ 8. pH 0 – 6.9 ______________________________ 9. vinegar ________________________________ 10. pH 7 - 14 ______________________________ 11. HCl ___________________________________ 12. produce ions in water ______________________

Answers 1. neutral 10. base 2. base 11. acid 3. acid 12. both 4. acid

1. An ________ is a compound that changes color in the presence of an acid or base. 2. This property of an acid can “eat away” certain metals_____________ 3. The ________ is a series of numbers that indicates the concentration of hydrogen ions in a solution. 4. A _______ is an ionic compound that forms from the reaction of an acid and a base. Vocabulary

5. At a pH near ________ stomach enzymes break down proteins. 6. During the neutralization process _______ and ________ is produced. 7. The process that breaks down complex molecules of food into smaller molecules is called________. 8. ____________ is the reaction between an acid and a base. 9. _________ digestion is a physical process in which large pieces of food are torn and ground into smaller pieces. 10. Most chemical digestion is completed in the ___.

Vocabulary Answers 1. indicator 2. corrosive 3. pH scale 4. salt 5. 2 (two) 6. salt and water 7. digestion 8. Neutralization 9. Mechanical 10. small intestines

pH Scale Range 0 – 14 Acids 0 – 6.9 (lower the number, stronger the acid) Bases 7.1 – 14 (higher the number, stronger the base) Neutral 7

Acid / Base Reactions Bases in water produce? Acids in water produce? 1. HCl Bases in water produce? 2. NaOH Acids and bases (neutralization) produce? 3. HCl + NaOH

Acid / Base Reaction Answers 1. H+ + Cl- 2. Na+ + OH- 3. H2O + Na+ + Cl-

More Practice! HCl + KOH  HF  LiOH  HF + LiOH  HBr  KOH  HCl + LiOH 

Answers HCl + KOH  KCl + H2O HF  H+ + F- LiOH  Li+ + OH- HF + LiOH  LiF + H2O HBr  H+ + Br- KOH  K+ + OH- HCl + LiOH  LiCl + H2O