Unit 13 Marker Board

Review

Acids & Bases

You need a marker board, marker, eraser, calculator, & periodic table.

Question #1

List 4 properties of acids.

Answer:1 – Sour taste2 – React with metals to form hydrogen gas3 – React with metal carbonates to form CO2 gas4 – Turn indicators red

Question #2

List 4 properties of bases.

Answer:1 – Taste bitter2 – Unreactive with metals and carbonates3 – Feel slippery4 – Turn indicator blue

Question #3

According to Arrhenius, acids ionize to produce _______ ions & bases ionize to produce _______ ions.

Answer:hydrogenhydroxide

Question #4

A Bronsted acid _____________ a _______________ and a base ______________ a ____________.

___________ is a substance that can either donate or accept a H+ ion.

Answer:- donates, hydrogen ion- accepts, hydrogen ion- Amphoprotic/Amphoteric

Question #5Label the Acid, Base, Conjugate Acid, &

Conjugate Base for each reaction below:

• NH3 + H2O NH4+ + OH-

• H2CO3 + H2O H3O+ + HCO3-

Answer:NH3 + H2O NH4

+ + OH-

B A CA CB

H2CO3 + H2O H3O+ + HCO3-

A B CA CB

Question #6

Strong acids ionize _______________ while weak acids ionize ________________.

Which is the stronger acid?

Oxalic Acid: Ka = 5.1 x 10-5

Carbonic Acid: Ka = 4.8 x 10-11

Answer:

completely; only partially;Oxalic Acid (larger Ka value)

Question #7

When an acid reacts with a base to neutralize it, the products are a ___________ & ___________.

Answer: Salt & Water

Question #8

List (write the formula for) the 6 strong acids.

Answer:

HCl

HI

HBr

HClO4

HNO3

H2SO4

Question #9

Acids have a pH ___________ than 7.

Bases have a pH __________ than 7.

Pure water has a pH of _____ because . . .?

Answer: Less

Greater

7 because it is neutral!

Question #10

• HBr• NaOH• HNO2

• H3PO3

• NH3

• H2SO4

• Mg(OH)2

• H2CO3

• HC2H3O2

Write the name for the following formulas. Is it an acid or base?Check your answers after you’ve written ALL of them!

Hydrobromic Acid—acid

Sodium Hydroxide—base

Nitrous Acid—acid

Phosphorous Acid - acid

Ammonia—base

Sulfuric Acid—acid

Magnesium Hydroxide - base

Carbonic Acid—acid

Acetic Acid—acid

Question #11

Write & balance the equation for the neutralization of sulfuric acid with potassium hydroxide.

Answer: H2SO4 + 2 KOH 2 H2O + K2SO4

Question #12

Write & balance the neutralization reaction of hydrobromic acid & calcium hydroxide.

Answer:

2 HBr + Ca(OH)2 2 H2O + CaBr2

Question #13

The formula for the hydronium ion is ____________________ & for the hydroxide ion _______________.

Answer: H30+ & OH-

Question #14

An H+ ion is really just a _______________ and cannot exist in solution.

Answer: Proton

Question #15

Write the equation for the self-ionization of water.

Answer: H2O + H2O OH- + H3O+

Question #16

The formula for calculating [H3O+] from pH is ______________________. I type this into my calculator as: _________

Answer: [H3O+] = 10^(-pH)

2nd log (negative pH)

Question #17

The formula for calculating [H3O+] from [OH-] is ______________________. I type this into my calculator as: _______

Answer: Kw = [OH-][H3O+] = 1.0 x 10-14

[H3O+] = 1.0 x 10-14

[OH-]

1.0 E -14 / [OH-]

Question #18

• List the formulas for pH, H+ concentration, pOH, & OH- concentration.

Answer:

pH = -log [H+] OR 14 - pOH[H+] = 10^(- pH) OR 1.0 x 10-14 / [OH-]pOH = -log [OH-] OR 14 - pH[OH-] = 10^(- pOH) OR 1.0 x 10-14 / [H3O+]

Question #19

• pH + pOH = ___________

•Answer: 14

Question #20

What is the pH of an HCl solution with a concentration of 0.0015 M? Acidic or basic?

•Answer: pH = -log (0.0015) = 2.8

Acidic

Question #21

• What is the pH of a solution with an pOH of 10.5? Acidic or basic?

Answer: pH = 14 – pOH = 14 – 10.5 = 3.5 Acidic

Question #22

• What is the [H+] of a solution with a pH of 4.51?

Answer: [H+] = 10^(-4.51) = 3.09 x 10-5 M

Question #23

• What is the pOH of a solution with a [H+] of 9.99 x 10-9 M? Acidic or basic?

Answer: pOH = -log [OH-]

[OH-] = 1.0 x 10-14 / 9.99 x 10-9 = 1.0 x 10-6 M

pOH = -log(1.0 x 10-6) = 6.0

pH = 14 – 6.0 = 8.0 Basic

Question #24

• What is the pOH of a solution with an [OH-] of 7.81 x 10-3 M? Acidic or basic?

Answer: pOH = -log [OH-] = -log (7.81x10-3) = 2.1

pH = 14 – 2.1 = 11.9 Basic

Question #25

• Calculate the [OH-] if the pOH is 5.21.

Answer: [OH-] = 10^(-5.21) = 6.17 x 10-6 M.

Question #26

What is the purpose of a titration? What is the role of an indicator in a titration? What has been reached when acid and base completely neutralize one another?

Answer: A titration enables you to determine the concentration of a solution by reacting a known volume of the solution with a solution of known concentration.

An indicator changes color when the end point of the titration has been reached.

The end point has been reached.

Question #27

• You add a substance to pure water and the pH rises from 7 to 9. What has happened to the concentration of H3O+? Is the substance added an acid or a base?

Answer: The concentration of H3O+ has decreased. The substance is a base.

Question #28

• In the titration of a strong acid with a strong base, what pH range should the indicator have?

Answer: 6-8

Question #29

• Write the balanced equation for the reaction between nitric acid and magnesium hydroxide.

Answer:

2 HNO3 + Mg(OH)2 Mg(NO3)2 + 2 H2O

Question #30

• What is the molarity of HNO3 if 15.0 mL is completely neutralized by 38.5 mL of 0.15 M Mg(OH)2?

Answer:

2 HNO3 + Mg(OH)2 Mg(NO3)2 + 2 H2O

MaVaCb = MbVbCaMa(15.0)( 1) = (0.15)(38.5)(2)Ma = 0.77 M