Quiz 2 - Chapter 15 and 16

Question 1

Acid vs Base

Answer 1

Acid: proton donor (H+), pH 0-6, sour, can dissolve metals, turns blue litmus paper red, neutralizes bases, citrus, vinegar, stomach acid
Base: proton acceptor (H+), pH 8-14, slippery, bitter taste, turns red litmus paper blue, neutralizes acids

Question 2

How to identify acids?

Answer 2

• H in front

- carboxylic acid= ends in -COOH

Question 3

How to identify bases?

Answer 3

• ends in OH
• also involves amines (N)
• group 1 or 2 metal with hydroxide

Question 4

Arrhenius definition of acids and bases

Answer 4

Acid: H+ donor
Base: OH- donor

Question 5

Bronsted-Lowry definition of acids and bases

Answer 5

Acid: proton (H+) donor
Base: proton (H+) acceptor

Question 6

Amphoteric

Answer 6

• substance can act as an acid or a base

- water is the most common

Question 7

Conjugate acid-base pairs

Answer 7

Two substances related to each other by transfer of a proton

Question 8

Acid ionization constant equation

Answer 8

Ka = concentrations of products / concentrations of reactants

Question 9

What happens to the reaction if:
A) Ka>1
B) Ka<1

Answer 9

A) when Ka>1, products are favoured, strong acid

B) when Ka<1, reactants are favoured, weak acid

Question 10

Characteristics of strong acids?

Answer 10

They completely dissociate (complete ionization) and have very large Ka values, weak attraction, Products is H30+

Question 11

What are some examples of strong acids?

Answer 11

HCl (hydrochloric acid)
HBr (hydrobromic acid)
HI (hydriodic acid)
HNO3 (nitric acid)
HClO4 (perchloric acid)
H2SO4 (sulfuric acid)

Question 12

Characteristics of weak acids?

Answer 12

Have small Ka value, only partially dissociate (partial ionization), reaction always has reversible arrows, strong attraction

Question 13

Characteristics of strong bases?

Answer 13

Completely dissociate (complete ionization), gives OH- as a product, have very large Kb values, weak attraction

Question 14

What are some examples of strong bases?

Answer 14

LiOH (Lithium hydroxide)
NaOH (Sodium hydroxide)
KOH (Potassium hydroxide)
Sr(OH)2 (Strontium hydroxide) 
Ca(OH)2 (Calcium hydroxide)
Ba(OH)2 (Barium hydroxide)

Question 15

Characteristics of weak bases?

Answer 15

Have small Kb value, only partially dissociate (partial ionization), reaction always has reversible arrows, strong attraction

Question 16

What is the equation for the water ionization constant? How does it apply to Ka and KB?

Answer 16

Kw=[H3O+][OH-]
Kw= 1.010^-14 at 25 degrees Celsius
Kw=KaKb (conjugate acid and conjugate base)

Question 17

What is the equation to calculate the pH using the concentration of H3O+? What about pOH?

Answer 17

pH=-log[H3O+]
pOH=-log[OH-]
14=pH+pOH

Question 18

How can you calculate the pH or pOH of a strong acid and a strong base? What about for a weak acid or base?

Answer 18

Concentration of strong acid=concentration of H3O+ then find pH
Concentration of strong base=concentration of OH- then find pOH
For weak acids or weak bases, you need to use ice tables to find concentrations of H3O+ or OH-

Question 19

What is the formula for calculating percent ionization? What is this formula also used to determine?

Answer 19

Percent ionization = [H3O+]eq / [HA]in *100
Used to see if we can make the x=0 assumption (must be below five percent to make this assumption!)
Percentage of the acid that ionizes (remember strong acids completely ionize, so this applies for weak acids!)

Question 20

Polyprotic acid

Answer 20

Have two or more protons that can dissociate. So must calculate in two steps! Usually are stronger acids (more H=more acidic)