Bell Ringer

What is the volume of one mole of a gas at STP?

Identify the pH associated with acids and bases.

Give two ways that acids are different from bases that does

not include their pH.

1. pH < 7.0

2. Electrolytes

3. Taste Sour

4. React with bases to form H2O + Salt

5. React with metals to form H2(g) and salt

Table J

1. pH > 7.0

2. Electrolytes

3. Taste Bitter

4. React with acids to form H2O + Salt

5. Slippery, soapy feeling

Arrhenius gives off an H+ and forms H3O+

- increases the H+ when dissolved in water

Bronsted proton [H+] donor (loses an H+) HCl

H+ + H2O

H+ + Cl-

H3O+

Arrhenius gives off an OH-

Bronsted proton [H+] acceptor (gains an H+)

NaOH

Ca(OH)2

Na+ + OH-

Ca+2 + OH-2

Chemicals which change colors when they are put into acids or bases.

These indicators change colors in response the [H+].

Table M

If you were to place H2SO4 onto a piece of copper, would it react to produce hydrogen gas? Explain your answer.

MAVA = MBVB

- Perform titrations to determine an unknown volume or concentration of an acid/base

- ENDPOINT = when indicator changes color

- Moles of H+ = Moles of OH-

- Products are always water and salt

MA= molarity of acid

VA= volume of acidMB= molarity of base

VB= volume of base

MAVA = MBVB

If 20.0ml of a 0.50M HCl solution is needed to neutralize 65.0ml of a NaOH solution. What was the concentration of the base?

MA= molarity of acid

VA= volume of acidMB= molarity of base

VB= volume of base

(0.5M)(20.0ml) = MB(65.0ml)

MB= 0.154M

MAVA = MBVB

43.0ml of HCl was titrated with 32.0 ml of 0.100 M NaOH. What is the molarity of the hydrochloric acid solution?

MA= molarity of acid

VA= volume of acidMB= molarity of base

VB= volume of base

MA(43.0ml)=(0.100M)(32.0ml)

MA= 0.0744 M

Conjugate PairsConjugate Pairs

HCl + KOH HOH + KClacid base conj. acid conj. base

Na2CO3 + 2HCl

base acid conj. acid conj. base

conj. base conj. acidacidbase

Strong acids have weak conjugate basesWeak acids have strong conjugate bases

H2O + H2SO4

H2CO3 + 2NaCl

HSO4- + H3O+

Identify the acid, base, conjugate acid, conjugate base, and conjugate acid-base pairs:

acid base conjugate acidconjugate baseHC2H3O2(aq) + H2O(l) C2H3O2

–(aq) + H3O+(aq)

conjugate acid-base pairs

acidbase conjugate acidconjugate baseOH

–(aq) + HCO3–(aq) CO3

2–(aq) + H2O(l)

conjugate acid-base pairs

Information related to an experiment is listed below:

H2SO4 + 2KOH K2SO4 + 2H2O

ResultsVolume H2SO4 used 12.0 ml

Concentration H2SO4 ?

Volume KOH used 36.0 mlConcentration KOH 0.16 M

Based on the above results, what is the concentration of H2SO4?

Setup for titrating an acid with a baseSetup for titrating an acid with a base

MAVA = MBVB

Calculate the molarity of an acetic acid solution if 34.57 mL of this solution are needed to neutralize 2.519 cL of 0.1025 M sodium hydroxide

MA= molarity of acid

VA= volume of acidMB= molarity of base

VB= volume of base

(MA)(34.57ml) = (0.1025M)(25.19ml)

MA= 0.07469M

Trial 1

Trial 2

Trial 3

Avg

Final Acid Volume

Initial Acid Volume

Final Base Volume

Initial Base Volume

Volume of Acid Used

Volume of Base Used

What are electrolytes?

Give two examples.

46) 25 mL47)3000 mL48)20 mL49)50.0 mL50)6.0 M51)0.60 M52)400 mL53)1.0 M54)SKIP

55)

H Cl

56)

H O

HH

+

57) O H

-

pH of Common pH of Common SubstancesSubstances

pH = -log[H+]If [H+] = 1 x 10-4, then pH =

- a way to measure the concentration of H+ ions (H3O+) in a solution

- concentration of H+ = [H+]

4

If [H+] = 1 x 10-13, then pH = 13

If [H3O+] = 1 x 10-7, then pH = 7

What is the pH of a 0.00001 molar HCl solution?

If the pH of your pool is 6, what is the concentration of hydronium ions in solution?

As the pH of a solution is changed from 3 to 6, how does the concentration of hydronium ions change?

An aqueous solution that a [H+] of 1.0 x 10-8 mole per liter has a pH of?

• Because it is a logarithmic scale, each one unit change in pH really represents a 10 fold change in [H+]

• So going from a pH of 6 to 7 really represents a 10 fold decrease in the number of [H+]

What is the difference in [H+] in a pool that has a pH of 6, but in reality you want it to have a pH of 7?

If [OH] = 10-8 M, what is the pH?

[H+][OH-] = 10-14

pH + pOH = 14

Solution:

• the OH = 8, so the pH must be 14 – 8

• So the pH = 6

Solution A has a pH of 1 and solution Z has a pH of 5.

How many times greater is the hydronium ion

concentration in solution A?

-A compound that does not allow the pH to change even if an acid or base is added to the system

-They have the ability to absorb/release H+ which will keep the pH relatively constant

-Good buffers are amphiprotic substances

-Amphiprotic – something that can act as an acid and a base

-Blood pH

-Adirondack lakes

Brooktrout Lake

"Treat the earth well: it was not given to you by your parents, it was loaned to you by your children. We do not inherit the Earth from our Ancestors, we borrow it from our Children."

Effects of Acid Rain on Marble(marble is calcium carbonate)

George Washington:BEFORE acid rain

George Washington:AFTER acid rain

The pH of a lake is 8.0. Over a 10 year period, the pH of the water

becomes 1000x more acidic.1. Name an ion that has increased in the water over the

10 years?

2. What is the pH now?

3. If you were to use bromothymol blue to test the pH, what color would it be? [Use R.T.]

1. H2O + H2O H3O+ + OH-2. H2SO4 + OH- HSO4

- + H2O3. HSO4

- + H2O SO4-2 +

H3O+4. OH- + H3O+ H2O + H2O5. NH3 + H2O NH4

+ + OH-

ACID BASE EQUATION

1 H2SO4 HSO4-

2 H3PO4

3 F-

4 NO3-

5 H2PO4-

6 H2O

7 SO4-2

8 HPO4-2

9 NH4+

10 H2O

H2PO4-

HFHNO3

HPO4-2

OH-

HSO4-

PO4-3

NH3

H3O+

H3PO4 ↔ H+ + H2PO4-

HF ↔ H+ + F-

HNO3 ↔ H+ + NO3-

H2PO4- ↔ H+ + HPO4

-2

H2O ↔ H+ + OH-

HSO4-↔ H+ + SO4

-2

HPO4-2 ↔ H+ + PO4

-3

NH4+4 ↔ H+ + NH3

H3O+ ↔ H+ + H2O

PART C26. A, C, D27. D28. Presence of H+ ions29. C30. C31. (10.01mL)(0.100M)= MB(5.01ml)

0.200 M32. 733. Colorless to pink.34. 0.21 M35. 0.97 M

36. Reduces error, increases reliability37. Ca(OH)2 + H2SO4 CaSO4 + 2H2O38. pH= 6.039. 0.33 M40. HCl – 9.50 ml NaOH – 3.80 ml41. 0.25 mL42. Methyl orange, brom blue, thymol blue

43. Between 4.4 and 5.544. Yellow

PART A1. 12. 33. 24. 45. 26. 37. 18. 29. 110. 411. 2

PART B

12. 413. 314. 415. 316. 117. 118. 119. 420. 221. 122. 323. 124. 225. 4

In a lab there were three flasks, one filled with methanol, another had NaOH, and the third HCl. ID these liquids.

TestTest Results

Bottle A Bottle B Bottle CMethyl orange Yellow Yellow YellowBromthymol Blue Blue Green YellowConductivity Conductor Nonconducto

r conductor

Reaction with Mg No Rxn No Rxn Rxn1. A student concluded that bottle C contained HCl.

Identify one way that supports this finding.

2. Explain in terms of pH, why methyl orange was the same for all three liquids.

What is the volume of 1.00 mole of any gas at STP?

Hint: Lab