Packet 9- Page 15 FLIPPED CLASSROOM NOTES. Acids and Bases

Transcription

1 Packet 9- Page 15 FLIPPED CLASSROOM NOTES Acids and Bases

2 Acids & Bases- Page 15 Ion an atom that carries a charge because it has lost or gained an electron Atom with more electrons than protons the atom becomes more negatively charged An atom with more protons than electrons the atom becomes more positively charged The more electrons an atom gains or loses, the more negative or positive it becomes.

3 Cation- Paws itively charged ion; lost electrons The letter t in cation looks like a positive plus sign +: ca+ion Ex: Hydrogen (H) can be a cation because it easily loses its one valence electron to become H + Ex. Element X as a cation: X + Anion- A Negative ION; gained electrons Ex: Chlorine (Cl) can be an anion because it easily gains an electron to become stable as Cl - Ex. Element X as an anion: X -

4 Acid A substance which when added to water produces hydrogen ions [H + ] The strength of an acid is based on the concentration of H+ ions in the solution. The more H + the stronger the acid. Characteristics of Acids: Taste sour React strongly with metals (Zn + HCl) Strong acids are dangerous and can burn your skin Corrosive - eat away at other materials! Examples of Acids: Vinegar Stomach Acid (Hydrochloric Acid- HCl) Citrus Fruits

5 The Power of Sour on Your Teeth: Acid Levels in Popular Sour Candies Water (neutral) 7.0 Loss of tooth enamel 4.0 Spree 3.0 Sweetarts 3.0 Sour Gummi Bears 3.0 X-treme Airheads 3.0 Sour Punch Straws 2.5 Shockers 2.5 Skittles 2.5 Baby Bottle Pop Powder 2.5 Brach s Gummi Bears 2.5 Wonka Laffy Taffy 2.5 Starburst 2.4 Sweet Tarts Shock 2.4 Lemon Heads 2.4 WarHeads Sour Rips Roll 2.3 Lollipop Paint Shop 2.2 Zours 2.2 Sour Skittles 2.2 Airheads Cherry Chew 2.0 Wonka Nerds Grape 2.0 Now and Later Cherry 1.9 Too Tart Extra Sour Goo 1.9 Wonka Pixy Stix Powder 1.9 Altoids Mango Sours 1.9 Wonka Fun Dip Powder 1.8 WarHeads Sour Spray 1.6 Battery acid 1.0 Data courtesy of Dr. John Ruby, University of Alabama Birmingham School of Dentistry, 2007.

6 ph of Soil- Hydrangea flowers In most species the flowers are white, but in some species, can be blue, red, pink, light purple, or dark purple. In these species (hyperaccumulating plants) the color is affected by the ph of the soil.

7 CHANGE TO PINK For hydrangea blooms to be pink, the plants must not take up aluminum from the soil. Shoot for a ph of about 6.0 to 6.2 CHANGE TO BLUE To obtain a blue hydrangea, aluminum must be present in the soil. To ensure that aluminum is present, aluminum sulfate may be added to the soil around the hydrangeas. ph of the soil should be low ( )

8 Base A substance which when added to water produces hydroxide ions [OH - ] The greater the concentration of Hydroxide ions [OH - ] the stronger the base. Ex. NaOH (Sodium Hydroxide-a strong base) in water Basic solutions are called alkaline Characteristics of Bases: Taste bitter Feel slippery Strong bases are very dangerous and can burn your skin Corrosive - eat away at other materials! Examples: lye (Sodium Hydroxide- NaOH) Ammonia

9 What do you think happens when you add an acid to a base? When acids and bases are combined, a process called neutralization occurs The acids and bases chemically react to create water (a neutrally charged substance) and a salt + HCl + NaOH H 2 O + NaCl

10 How can you tell the difference between an acid and a base? ph Scale- Potential for Hydrogen Scale; measures acids and bases = acid 7 = neutral substance = base Litmus paper- indicator paper that changes colors to tell whether a substance is an acid or a base Acids - turn the paper a shade of red/orange Bases - turn the paper a shade of blue/green

11 Acids vs. Bases (ph Scale) Acids are materials that have a higher concentration of H + ions They are measured from on the ph scale Bases are materials with a lesser concentration of H + ions, and a greater concentration of OH - ions They are measured from on the ph scale