Name ______Date ______Class ______

Acids & Bases Notes Activity

Cut out and assemble your “Acids & Bases Notes” sheet so that you have one long sheet.

STEP 1 – pH scale and pOH scale

Cut out the boxes on the first four rows on the “Cut out sheet.” Then, using the clues below, place each piece you just cut out into the proper box on your “Acids & Bases Notes” sheet

CLUES (Step ONE):

  • The pH scale ranges from 0-14.
  • Any substance with a pH of a 7 is a neutral substance having neither properties of an acid or a base.
  • Any substance with a pH below 7 is an acid and has the following properties: taste sour, feel like water but concentrated acids can cause skin burns, turn blue litmus paper red.
  • The lower the pH, the stronger the acid. Therefore, an acid with a pH of 3 is stronger than an acid with a pH of 4.
  • Any substance with a pH above 7 is a base and has the following properties: taste bitter, often feels slippery or soapy but concentrated bases can cause skin burns, turns red litmus paper blue.
  • The higher the pH, the stronger the base. Therefore, a base with a pH of 9 is stronger than a base with a pH of 8.
  • Since the acids and bases dissociate into H+ and OH-, if the pH is high, the pOH is low. Therefore, the pOH scale will run directly opposite of the pH.

STEP 2 – Basic Properties & Strengths of acids & bases

Cut out theboxes on the next two rows on the “Cut out sheet.” Then, using the clues below, place each piece you just cut out into the proper box on your “Acids & Bases Notes” sheet

CLUES (Step ONE):

  • Any substance with a pH below 7 is an acid and has the following properties: taste sour, feel like water but concentrated acids can cause skin burns, turn blue litmus paper red.
  • The lower the pH, the stronger the acid. Therefore, an acid with a pH of 3 is stronger than an acid with a pH of 4.
  • Any substance with a pH above 7 is a base and has the following properties: taste bitter, often feels slippery or soapy but concentrated bases can cause skin burns, turns red litmus paper blue.
  • The higher the pH, the stronger the base. Therefore, a base with a pH of 9 is stronger than a base with a pH of 8.

STEP 3 – Ion concentrations of acids & bases

Cut out the boxes on the next six rows on the “Cut out sheet.” Then, using the clues below, place each piece you just cut out into the proper box on your “Acids & Bases Notes” sheet

CLUES (Step TWO):

  • pH stands for the “power of Hydrogen” and is a measure of the concentration of hydrogen ions (H+) in a solution of the substance.
  • The strongest base has the lowest concentration of hydrogen ions (H+).
  • The lower the concentration of hydrogen ions (H+), the stronger the base.
  • The strongest acid has the highest concentration of hydrogen ions (H+).
  • The higher the concentration of hydrogen ions (H+), the stronger the acid.
  • Since the acids and bases dissociate into H+ and OH-, if the pH is high, the pOH is low. Therefore, the pOH scale will run directly opposite of the pH.

STEP 4 – Common acids & bases

Cut out the boxes on the last rows on the “Cut out sheet.” Then, using the clues below, place each piece you just cut out into the proper box on your “Acids & Bases Notes” sheet

CLUES (Step THREE):

  • Water is neutral.
  • The strongest acid is found in cars.
  • Acids are typically found in substances that people drink.
  • The strongest base unclogs your sink.
  • A very weak base we swim in at the beach has a hydrogen ion concentration of 1/10.
  • Our body eliminates this very weak acid.
  • The second strongest acid is a compound composed of a 1:1 ratio of hydrogen and chlorine atoms.
  • Your bath tub may have a pH of 12.
  • Your favorite drink has 10,000 times more H+ ions than water.
  • Bleach is stronger than ammonia.
  • Lemons are stronger than tomatoes.
  • Baking soda has a pH that is .01 the strength of pure water.
  • Tomato Juice is stronger than a popular morning caffeinated drink.
  • If you have an upset stomach, you may take something with a pH of 10.

Name ______Date ______Class ______

pH Cut and Paste Activity Questions

  1. Which solution from the activity is the strongest acid? ______Strongest base? ______
  1. List the solutions you would expect to taste bitter: ______, ______,

______, ______, ______, ______, and

______. Explain why you think these solutions would taste bitter. ______

______

  1. List the solutions you would expect to taste sour: ______, ______,

______, ______, ______, ______, and

______. Explain why you think these solutions would taste sour. ______

______

  1. List the solutions you would expect to feel slippery: ______, ______,

______, ______, ______, ______, and

______. Explain why you think these solutions would feel slippery. ______

______

  1. Classify the following substances as an acid or a base:

Eggs (pH = 7.9) ______Bananas (pH = 5.3) ______

Shampoo (pH = 5.8)______Stomach Acid (pH = 1.0) ______

Vinegar (pH = 3.0)______Blood (pH = 7.2) ______

  1. Put the acids from question #5 in order of strongest to weakest:

______

Strongest Weakest

  1. Put the bases from question # 5 in order of strongest to weakest:

______

Strongest Weakest

  1. Which substance from question # 5 has the lowest hydrogen ion concentration? ______
  1. Which substance from question # 5 has the highest hydrogen ion concentration? ______

10. What do you notice about the sum of the pH and pOH values for each substance? ______

11. Calculate the pH of a solution having a hydrogen ion concentration of 1.37 x 10-2M. pH = ______

12. Calculate the pOH of a solution with a hydroxide ion concentration of 2.5 x 10-5M. pOH= ______

13. Calculate the pH of a solution having a hydrogen ion concentration of 6.37 x 10-4M. pH =______

14. Calculate the pOH of a solution with a hydroxide ion concentration of 8.33 x 10-9M. pOH= ______

15. Calculate the pOH of a solution with a hydroxide ion concentration of 4.60 x 10-2M. pOH= ______

16. Calculate the pH and pOH of a solution with a hydroxide ion concentration of 3.2 x 10-9M. pH =_______

pOH = ______

17. Calculate the pH and pOH of a solution with a hydrogen ion concentration of 1.34 x 10-6M. pH =_______

pOH = ______

18. Calculate the pH and pOH of a solution with a hydroxide ion concentration of 6.4 x 10-3M. pH =_______

pOH = ______

19. If a substance has a pH of the following, what will be the pOH? What will each be, acid, base, or neutral?

  1. pH = 7; pOH = ______ACID, BASE, or NEUTRAL?

CIRCLE ONE

  1. pH = 3.2; pOH = ______ACID, BASE, or NEUTRAL?

CIRCLE ONE

  1. pH = 10; pOH = ______ACID, BASE, or NEUTRAL?

CIRCLE ONE

  1. pH = 1.4; pOH = ______ACID, BASE, or NEUTRAL?

CIRCLE ONE

  1. pH = 12.3; pOH = ______ACID, BASE, or NEUTRAL?

CIRCLE ONE

20. If a substance has a pOH of the following, what will be the pH?

  1. pH = 6.85; pOH = ______ACID, BASE, or NEUTRAL?

CIRCLE ONE

  1. pH = 13.4; pOH = ______ACID, BASE, or NEUTRAL?

CIRCLE ONE

  1. pH = 5.5; pOH = ______ACID, BASE, or NEUTRAL?

CIRCLE ONE

  1. pH = 3.4; pOH = ______ACID, BASE, or NEUTRAL?

CIRCLE ONE

  1. pH = 14; pOH = ______ACID, BASE, or NEUTRAL?

CIRCLE ONE

PROPERTIES:

pH
value / pH
value / pH
value / pH
value / pH
value / pH
value / pH
value / pH
value
H+ Concentration / H+ Concentration / H+ Concentration / H+ Concentration / H+ Concentration / H+ Concentration / H+ Concentration / H+ Concentration
p[OH]
value / p[OH]
value / p[OH]
value / p[OH]
value / p[OH]
value / p[OH]
value / p[OH]
value / p[OH]
value
OH- Concentration / OH- Concentration / OH- Concentration / OH- Concentration / OH- Concentration / OH- Concentration / OH- Concentration / OH- Concentration
Example / Example / Example / Example / Example / Example / Example / Example

Types of Acids & Bases

Arrhenius Acids

______

HCl(g)  H+(aq) + Cl-(aq)

Arrhenius Bases

 ______

NaOH(s)  Na+(aq) + OH-(aq)

Bronsted-Lowry Acid

______

HF + H2O  H3O+ + F-

Bronsted-Lowry Base

______

NH3 + H2O  NH4+ + OH-

Amphoteric

______

Strength of Acids & Bases

 The strength of an acid or base depends on how COMPLETELY a compound separates into its ions when dissolved in water

STRONG ACID

Almost ionized completely in solution

WEAK ACID

Partly ionizes in solution

STRONG BASE

Dissociates completely in solution

WEAK BASE

Does not ionize completely in solution

Strong acids and bases conduct MORE electricity than weak ones

Acid & Base Equations

Equations for strong acids and bases use a single arrow, indicating ions are formed.

HCl + H2O  H3O+ + Cl-

NaOH  Na+ + OH-

Equations for weak acids and bases use double arrows, pointing in opposite directions, indicating an incomplete reaction.

Ca(OH)2  Ca2+ + 2OH-

HC2H3O2 + H2O  H3O+ + C2H3O2-

Concentrations of Acids & Bases

“Dilute” and “concentrated” are terms used to describe the amount of acid or base dissolved.

Dilute

few molecules of an acid or base dissolved in a volume of solution.

Concentrated

many molecules of an acid or base dissolved in a volume of solution.

pH

pH-a scale used to classify acids and bases

the pH scale ranges from 0-14

acids have a pH below 7

bases have a pH above 7

neutral substances have a pH of 7

Ions in solution

Acidic solutions have more hydrogen ions than hydroxide ions.

Basic solutions have more hydroxide ions than hydrogen ions.

Neutral solutions have an equal number of hydrogen ions and hydroxide ions.

PROPERTIES:

pH
value / pH
value / pH
value / pH
value / pH
value / pH
value / pH
value
H+ Concentration / H+ Concentration / H+ Concentration / H+ Concentration / H+ Concentration / H+ Concentration / H+ Concentration
p[OH]
value / p[OH]
value / p[OH]
value / p[OH]
value / p[OH]
value / p[OH]
value / p[OH]
value
OH- Concentration / OH- Concentration / OH- Concentration / OH- Concentration / OH- Concentration / OH- Concentration / OH- Concentration
Example / Example / Example / Example / Example / Example / Example

Acids

Characteristically have ______

Examples:

Properties of Acids

tastes ______

______& can damage ______

feel like ______, except on broken skin

react with an ______(such as litmus or pH paper) to produce a ______

turns ______

react with ______to produce ______

______

Common Acids

 Foods contain Acids

______acid – ______

______acid – ______

______acid (______) – ______

The stomach uses ______

Industrial Acids

______acid

Used in ______

______acid

Used to ______

______acid

Used to make ______

______acid

Used to ______

Bases

Characteristically have ______

Examples:

Properties of Bases

tastes ______

many are ______

strong bases can be ______& can damage ______

feel ______

react with an ______(such as litmus or pH paper) to produce a ______

turns ______

dissolves in water to form an ______

Common Bases

 Bases have different uses:

______

______

______

______

CUT OUT SHEET

pH 0 / pH 1 / pH 2 / pH 3 / pH 4 / pH 5 / pH 6 / pH 7
pH 8 / pH 9 / pH 10 / pH 11 / pH 12 / pH 13 / pH 14
pOH 0 / pOH 1 / pOH 2 / pOH 3 / pOH 4 / pOH 5 / pOH 6 / pOH 7
pOH 8 / pOH 9 / pOH 10 / pOH 11 / pOH 12 / pOH 13 / pOH 14
TASTE SOUR / TASTE BITTER / FEELS LIKE WATER / FEELS SLIPPERY/SOAPY / TURNS BLUE LITMUS PAPER RED / WEAK ACID / STRONG ACID
CONCENRTATED ACIDS CAN CAUSE SKIN BURNS / CONCENRTATED BASES CAN CAUSE SKIN BURNS / TURNS RED LITMUS PAPER BLUE / WEAK BASE / STRONG BASE
Hydrogen ion (H+) Concentration
10,000,000 / Hydrogen ion (H+) Concentration
1,000,000 / Hydrogen ion (H+) Concentration
100,000 / Hydrogen ion (H+) Concentration
10,000 / Hydrogen ion (H+) Concentration
1,000 / Hydrogen ion (H+) Concentration
100 / Hydrogen ion (H+) Concentration
10 / Hydrogen ion (H+) Concentration
1
Hydrogen ion (H+) Concentration
1/10,000,000 / Hydrogen ion (H+) Concentration
1/1,000,000 / Hydrogen ion (H+) Concentration
1/100,000 / Hydrogen ion (H+) Concentration
1/10,000 / Hydrogen ion (H+) Concentration
1/1,000 / Hydrogen ion (H+) Concentration
1/100 / Hydrogen ion (H+) Concentration
1/10
Hydroxide (OH-) Concentration
1/100 / Hydroxide (OH-) Concentration
1,000,000 / Hydroxide (OH-) Concentration
1/1,000 / Hydroxide (OH-) Concentration
100,000 / Hydroxide (OH-) Concentration
1,000 / Hydroxide (OH-) Concentration
100 / Hydroxide (OH-) Concentration
10,000,000
Hydroxide (OH-) Concentration
10 / Hydroxide (OH-) Concentration
1/1,000,000 / Hydroxide (OH-) Concentration
1/100,000 / Hydroxide (OH-) Concentration
1/10,000 / Hydroxide (OH-) Concentration
1/10,000,000 / Hydroxide (OH-) Concentration
1 / Hydroxide (OH-) Concentration
1/10 / Hydroxide (OH-) Concentration
10,000
Hydrogen Ion (H+) Concentration Decreases   /   Hydrogen Ion (H+) Concentration Increases
Hydroxide Ion (OH-) Concentration Decreases   /   Hydroxide Ion (OH-) Concentration Increases
Battery
Acid / Soda / Bleach / Urine / Ocean
Water / Lemon
Juice / Ammonia / Liquid Drain
Cleaner
Coffee / Soapy
Water / Pure
Water / Milk of Magnesia / Baking Soda / Tomato
Juice / Hydrochloric
Acid (HCl)

Calculating pH

 pH is the negative logarithm of the hydrogen ion concentration

pH = -log [H+]

Calculate the pH of a solution having a hydrogen ion concentration of 1.0 x 10-2 M.

pH = -log [H+]; pH = -log[1.0 x 10-2]; pH = 2

Calculating pOH

pOH

the negative logarithm of the hydroxide ion concentration

pOH = -log[OH-]

Calculate the pOH of a solution with a hydroxide ion concentration of 1.0 x 10-6M.

pOH = -log[OH-]; pOH = -log[1.0 x 10-6]; pOH = 6

Relationships between pH and pOH

pH + pOH = 14; pH = 14 – pOH; pOH = 14 – pH

PRACTICE CALCULATING pH

Calculate the pH and pOH of the a solution with a hydroxide ion concentration of 3.2 x 10-9M.

pOH = -log[pOH]

pOH = -log[3.2 x 10-9]; pOH = 8.49

pH = 14 – pOH

pH = 14 – 8.49; pH = 5.51

Neutralization

Neutralization

chemical reaction between an acid and a base in an aqueous solution producing a salt and water

a double replacement reaction.

Salt

ionic compound made up of a cation from a base and an anion from an acid.

Mg(OH)2 + HCl  MgCl2 + 2H2O

Titration

Titration

used to determine the concentration of an acidic or basic solution

A solution of known concentration is the standard solution.

An acid/base indicator is added to the unknown solution.

A color change that persists is the end point.